April 25th, 2013 
CryptoBadger In this fifth and final installment of our litecoin mining rig guide, I’ll answer some common questions about building your own rig, profit expectations, and mining in general. If you’ve read the rest of the guide and still have some lingering questions, you might find the answers you’re looking for here.
Hit the “read more” button for the FAQ!
Build a Litecoin Mining Rig, part 5: Mining FAQ
General Questions
- So how much money can I expect to make from mining, exactly?
- Why not just buy litecoins (or bitcoins) directly, and then sell them later at a profit?
- How noisy/hot are these rigs?
- How do I convince my significant other that building a rig is a good idea?
Technical Questions
- How do I turn my computer on without a case/power switch?!
- Why the Radeon 7950 GPU? Why not a 7970, or another video card entirely?
- Why stop at 3 GPUs? Can’t I pack 4-5 (or more) onto one motherboard?
- Can I get PCI-E risers anywhere locally? The ones that are linked in guide ship from Hong Kong.
- Don’t I need more than 4GB of RAM? I read other guides that say I need 1.5GB per GPU, minimum.
- My kill-a-watt shows power consumption spiking up to nearly 900 watts at times, on my 860 watt power supply. Isn’t that bad?
- Can I utilize my mining rig for anything else while it’s mining?
- How much of my internet bandwidth will my mining rig use?
- I’m getting “Error -5: Enqueueing kernel onto command queue.” when running cgminer. How do I fix this?
- I’m getting an error complaining about “libjansson.so.4” on linux. What do I do?
- Cgminer is complaining about a missing shared library file: libudev.so.1. What now?
- I have another brand of 7950 video card. Do you know what cgminer settings to use?
Other
Answers
So how much money can I expect to make from mining, exactly?
This is the question that most people are interested in. The answer is fairly complicated, and changes daily.
Today, one litecoin is worth just over $4. A few weeks ago, that same litecoin peaked at a value of just over $6. A month before that, litecoins were trading at 6 cents apiece. The volatility in digital currency value is extreme—the price today could be very different than the price tomorrow.
On top of that, the difficulty involved with mining a coin is also changing constantly. Today, the rig in our guide will produce about 5 litecoins a day. A month ago, it would have produced ~20/day. The more people mining, the more time/computing power it takes to produce a coin.
You can answer the question for right now by using a calculator such as this one. If you’re building the exact rig outlined in the guide, plug in 1900 in the box next to “scrypt”, make sure that “kH/sec” is selected, plug in 800 for “power” (or 700 if you plan to undervolt), and then plug in your electricity rate. Make sure that the time period you’re interested in is selected (day, week, month). The calculator takes into account the current mining difficulty.
At the time of this writing, assuming you pay $0.08 per kWh for electricity, the calculator would tell you that you should expect to make about $580 per month from your mining rig. Remember to subtract 1-2 percent for your mining pool’s fee. Taking off another couple percent for downtime and other unexpected issues is probably a good idea, too.
If the price of litecoins rises faster than the mining difficulty increases, then that profit figure will increase. If the mining difficulty outpaces the value growth of litecoin (and/or litecoin drops in value), then profit will decrease.
Since it is very difficult to predict the future, I’d strongly advise everyone reading this to treat mining as a hobby, and not a “get rich quick” scheme. Only invest what you’re comfortable losing, because losing is a very real possibility.
Why not just buy litecoins (or bitcoins) directly, and then sell them later at a profit?
If you believe that litecoins are about to shoot up in value, and you have a very high tolerance for risk, and you have some money that you won’t miss if it suddenly disappears, then this might be the best idea for you. Buying the digital currency directly enables you to get your hands on a bunch of it quickly, without having to wait for a mining rig to produce it for you. However, the “sell them later at a profit” part doesn’t always work out. =)
For most of us with a desire to jump into cryptocurrency, mining is probably the safer option. If you buy $1500 worth of litecoins today, and tomorrow they become worthless (and never recover), then you’ve lost $1500. If you purchase a $1500 mining rig today, and tomorrow litecoins are worthless, then you still have $1500 worth of hardware. You can sell it at a small loss, or re-purpose it (maybe try your luck at mining one of the other digital currencies, for example).
This is difficult to answer because it’s so subjective. I will say that an open-air mining rig with three AMD 7950 GPUs in it will certainly not be “quiet”. If you’re planning to occupy the same space as your rig, you may very well find the noise unpleasant. I’d suggest in that case that you purchase the Sapphire Vapor-X brand of 7950, as they are significantly less noisy than most brands.
The heat that a rig produces may be more of an issue, depending on where you live. I live in the northeast US, and in the winter, my rigs double as space heaters—I can easily heat a small room with one. In the summer, the extra heat is a nuisance.
Ideally, you have someplace that you can tuck your rig(s) where they’re out of earshot. Basements and garages are both good ideas if they’re relatively clean and temperatures don’t venture into extremes.
How do I convince my significant other that building a rig is a good idea?
You’re on your own with that one. Good luck! =)
How do I turn my computer on without a case/power switch?!
So you didn’t opt to purchase a power switch, and now you’re sitting there staring at a bunch of assembled hardware, and wondering how the heck to turn the thing on for the first time. Don’t worry, you have a couple options.
If you bought the motherboard from our guide, then there is a power button built right onto the motherboard. This is increasingly common these days, so even if you have another motherboard, check to see if there is a built-in switch.
If you don’t have a button on your motherboard, then grab a flathead screwdriver. Now use the head of your screwdriver to temporarily short the two pins on the motherboard that the power switch would be connected to (if you had a power switch). Just touch the head of the screwdriver so that it makes contact with both pins for a brief moment. Your system should immediately power on.
The first thing you should do at this point is enter the BIOS and change the power options to set your computer to automatically power on whenever power is restored. That way, you can use the switch on your power supply to turn it on and off going forward.
Why the Radeon 7950 GPU? Why not a 7970, or another video card entirely?
The AMD 7950 GPU is currently gives the best hashrate/watt ratio, and also has an excellent hashrate/purchase price ratio. It’s really the ideal GPU for mining, at least for now.
The 7970 does give (slightly) better overall hashrates, but it consumes more power, and costs significantly more. The 7850 is a nice budget option from a purchase price standpoint, but it’s significantly less powerful than the 7950, and it’s hashrate/watt ratio is worse, too.
Nvidia GPUs are out entirely, as they’re just terrible for mining.
Why stop at 3 GPUs? Can’t I pack 4-5 (or more) onto one motherboard?
I like the way you think!
Yes, it is certainly possible to cram 4, 5, even 6 or more GPUs onto a single motherboard. You can actually make use of the 1x PCI-E slots on your motherboard to connect additional GPUs via 1x to 16x riser cables (you wouldn’t do this for gaming or other applications, but mining performance won’t be impacted at all by using a 1x PCI-E slot).
There are some things to be aware of, though.
First, if you plan to go beyond 3 GPUs, you’ll need to use powered PCE-E risers (something like this). Each 7950 GPU will draw 75 watts from the motherboard (and the remaining from the PCI-E power connectors to your power supply). Asking a motherboard to deliver 75 watts for more than 3 GPUs is very likely asking too much—you risk a fried motherboard if you use unpowered risers (like the ones in our guide) for more than 3 video cards. You can also use one of these to supply additional power to your motherboard for a 4th GPU, but you give up a PCI-E slot to do so.
Second, 4 GPUs is the limit in Windows. You’ll run into all sorts of strange issues if you try to add more than that. You’ll need to use Linux if you want to pack 5+ GPUs into a single system.
Finally, you’ll need a bigger power supply. For each additional GPU, add another ~200 watts onto the PSUs rating.
The rig in our guide can easily be expanded accommodate a 4th 7950 GPU by upgrading the PSU and either using one powered 1x to 16x riser or an unpowered riser and an EVGA Power Boost. You may also want to get a larger 6-gallon crate if you’re planning to run a 4+ GPU rig.
Can I get PCI-E risers anywhere locally? The ones that are linked in guide ship from Hong Kong.
Updated 5/8: The guide has been updated to link to fairly cheap risers available on Amazon. If you’re buying in bulk, eBay might still be slightly cheaper.
I haven’t been able to find any risers outside of Hong Kong or China for reasonable prices. I ordered a set from a Boston-based business, but they still shipped from Asia. Ebay is probably your best bet, here. The ones I ordered arrived in about 10 days, and they were decently high-quality (well made with locking clips on both ends). The eBay seller that I purchased from is linked to in the hardware guide.
You can run your GPUs directly off the motherboard while you’re waiting for your risers to arrive by setting up a box fan to blow air between them. They’ll still run pretty hot, though.
Don’t I need more than 4GB of RAM? I read other guides that say I need 1.5GB per GPU, minimum.
Cgminer uses the memory on your GPUs, so you don’t need much system memory at all. You can get by just fine with 1-2GB of RAM in Linux, and 4GB is plenty in Windows.
If you read other guides telling you that you need a ton of system RAM, the author was probably running Reaper as their mining software, which oddly uses system memory.
My kill-a-watt shows power consumption spiking up to nearly 900 watts at times, on my 860 watt power supply. Isn’t that bad?
If you’re not undervolting, but you are overclocking, then it’s possible that you’ll see power consumption numbers this high (or even higher), depending on how efficient your PSU is.
The number that your kill-a-watt shows you is the “at the wall” power consumption—basically, how much electricity you’re actually using.
The number that power supplies are rated for is how much they’re capable of delivering to your system components. This number is after accounting for efficiency loss. For example, the Seasonic PSU that I recommend delivers 860 watts and is 93% efficient (which is excellent). That means that when it is delivering 100% of it’s rated power, it will actually be pulling 925 watts at the wall (860w / .93). High-quality PSUs are typically capable of delivering more than their rated power without issues, as well.
This is why it’s so important to buy a high-quality power supply for a computer that is going to be running 24/7, especially if electricity is particularly expensive in your area. An 80% efficient PSU would pull 1075 watts at the wall when delivering 860 watts to a computer—a full 150 watts more than the 93% efficient Seasonic!
Can I utilize my mining rig for anything else while it’s mining?
It’ll make a great space heater in the winter. =) Oh, you mean application-wise.
The CPU, memory, and disk will mostly be unused while your rig is mining, but anything GUI-related will be pretty unresponsive. Applications that run in the background or over the network are good candidates, if you’re looking to get some extra use out of your rig. You should be able to run things like file servers and low-traffic web servers just fine without impacting mining performance.
How much of my internet bandwidth will my mining rig use?
Not much at all. Mine averages around 30 kb/sec when it’s mining at full speed, which is less than half of one percent of the average broadband speed in the US (~6.6 mb/sec). Bandwidth is basically a non-issue—you could run a mining rig off a dial-up connection.
I’m getting “Error -5: Enqueueing kernel onto command queue.” when running cgminer. How do I fix this?
You’re probably running a 32-bit OS (I highly recommend using a 64-bit OS for mining if it all possible). At least, that’s the only time I’ve seen this error pop up. Try changing your cgminer startup script to these parameters:
cgminer --scrypt -I 13 -g 2 -w 256 -v 1 --thread-concurrency 8192 -o [POOL] -u [USERNAME] -p [PASSWORD]You may not hit quite the same performance level as you would using the settings I give in my optimization guide, but hopefully this will get you running. If it doesn’t, try also installing the latest Catalyst driver & SDK.
I’m getting an error complaining about “libjansson.so.4” on linux. What do I do?
If you’ve followed my guide exactly, you shouldn’t run into this issue. However, if you’re running a different distro, or another version of Xubuntu, it’s possible that you might encounter this.
To resolve, simply enter this on the command line:
ln -s /usr/local/lib/libjansson.so.4 /usr/lib/libjansson.so.4Cgminer is complaining about a missing shared library file: libudev.so.1. What now?
If you downloaded a more recent version of cgminer than the one that I linked in my guide, this issue might affect you. The error message you’ll see looks something like “error while loading shared libraries: libudev.so.1: cannot open shared object file: No such file or directory.” To resolve this issue, you’ll need to run the following command:
sudo ln -s /lib/x86_64-linux-gnu/libudev.so.0 /lib/x86_64-linux-gnu/libudev.so.1If that doesn’t work for you, try this:
sudo ln -s /lib/x86_64-linux-gnu/libudev.so.0.13.0 /lib/x86_64-linux-gnu/libudev.so.1I have another brand of 7950 video card. Do you know what cgminer settings to use?
If you have a Gigabyte WF3 7950, make these substitutions in your cgminer startup script when following my optimization guide (leave everything else the same):
--thread-concurrency 25984 --gpu-engine 1065 --gpu-memclock 1500
If you have a Sapphire Vapor-X 7950, make these substitutions in your cgminer startup script when following my optimization guide (leave everything else the same):
--thread-concurrency 24000 --gpu-engine 1095 --gpu-memclock 1250
If you also follow my undervolting guide, you can use 1037 mV in place of the 1081 mV I recommend on the Sapphire card (and possibly go even lower, but 1037 has always been stable for me).
If you have another brand and are looking for settings, I recommend the bitcointalk forums or the litecoinmining subreddit.
Can I buy you a beer? Your mining guide has been a huge help!
Certainly! Well, virtually, anyway. I’d be happy to accept donations at the below wallet addresses:
Bitcoin: 1DpnANRtMDPe8jG3FXfkyczLFevM94Yjxv
Litecoin: LPuwBa3LbZZzcJaR3kEsGDBivAoc64fPUr
And thanks! =)
Posted in 
Great guide!
I count 5 PCI-e slots of that MB. Wouldn’t that MB support up to a total of 5 GPUs so long as two of them were running off powered risers?
Is 5 PCI-e slots the max for motherboards? Haven’t found any with more slots.
That’s correct; you should be able to run 5 GPUs off this board as long as a couple risers are powered and you use a bigger PSU.
I believe I saw a motherboard with 6 PCI-E slots at some point, but I’m not sure I’ve ever seen anyone run that many GPUs off one. I know quite a few people run five, though.
Hi! Loving the guide so far and am planning on building a couple of 4 gpu rigs based on your guide. Just to clarify though, to add the 4th card I just need 1 powered riser, correct? Is there any advantage to using all powered risers? I was planning on using Seasonic X-1250 1250W 80Plus Gold EPS12V / ATX12V as the psu… is this a good choice? How about if I end up adding a 5th card? (Definitely running Ubuntu). You truly deserve some kind of medal for this blog, but there will certainly be some litebeers coming your way from my direction!
Whoops sorry about the psu question… just looked below and read about it… duh. I am wondering about the powered risers still though… I have read some debate about it and never seen a definitive answer.
Yes, for four GPUs you’ll need one powered riser. There is no advantage to using all powered risers, although it won’t hurt anything either (they’re slightly pricier than unpowered risers, though). For five GPUs, you’ll need 2 powered risers.
The Seasonic 1250w is a great choice for 4 GPUs. For 5 GPUs, you’ll probably want to consider the Lepa 1600w. Good luck with your build!
Thanks for the quick reply. One more question if you don’t mind. Would that upgraded Corsair 1200 be enough for 5 GPU’s or should one upgrade the PSU even further?
I seem to see lots of 4 card system on the forums. I’m wondering if 4 card GPU systems seem to be the sweet spot and that adding more GPU’s to one MB might require some undervolting to keep from frying stuff…
1200 watts would be pushing it for 5 GPUs. If you’re undervolting, you should be ok, but I usually recommend a quality 1250w as the absolute minimum for 5.
I think the reason that 4 GPUs is popular is that is generally the limit for windows. You can get more than 4 GPUs working in windows, but it’s usually a headache. A lot of people aren’t comfortable with linux (which has no issues with 5+ GPUs), so they stop at 4.
The only decent 1250w power supply I have seen is this one: http://www.amazon.com/Seasonic-SS-1250XM-ATX-Power-Supply/dp/B00607JLWU/ref=sr_1_2?s=electronics&ie=UTF8&qid=1367675641&sr=1-2&keywords=1250+power+supply
But it’s only gold certified so it is a few percent less efficient than a platinum. Decisions Decisions. Can’t figure out if I want a 5 GPU setup on one board or have two MB setups each having 4 GPUs…
Yes, that PSU is usually the one I recommend for 4-5 GPU setups. Unfortunately the larger PSUs are usually a bit less efficient.
Thanks again for the great guide, I’m just wondering if the upgraded power supply is more noisy? I’ll be running it in the room next to the bedroom, with fairly thin walls, would that be ok do you think noise wise? (hard to describe noise levels I know!)
The PSU is probably the quietest component in the rig, even if you get a larger 1200+ watt unit (assuming you get a quality one – the Corsair and this Seasonic should both be fine).
If you use the same settings that I outline in my optimization guide (including managing the fans and temperature target for reduced noise), I don’t think you’ll hear the rig if it’s in an adjacent room, unless that room is very hot (which would cause the fans to work harder to maintain your target temperature). Basically, aim to keep the GPU fans at 50% or less if you’re concerned with noise.
The Sapphire Vapor-X GPU that you recommend for the most quiet running, is that able to be undervolted?
I do not have one myself so I cannot say for sure, but from reading about other peoples’ experiences with Sapphire cards on the bitcointalk forums and reddit, I wouldn’t expect it to be voltage-locked.
I can confirm that the Vapor-X are actually quite a loud card. I have compared these to 3 other HD7950 cards running at max capacity. The Vapor-X fans are loud and I would not recommend you locate a rig in your Living area if you go for the Vapor-X.
I recommend Sapphire Flex HD7950 if you want quieter fans with a decent hash rate. I am getting circa 650 kh/s for litecoin.
Thank you. I have not started building yet, bit I do have all the parts now. For the record this is the GPU that I got:
http://www.amazon.com/gp/product/B009MML1UA/ref=oh_details_o04_s01_i01?ie=UTF8&psc=1
It does have very good reviews for being quiet, so I am hopeful, however having never built a rig or gaming computer before, I really don’t have anything to compare it to. However, once my rigs are set up, I am very clear that the “loving space” will no longer be my living space. I am prepared for that. My choice for that room is because it is decidedly colder there than any other room in the house. Living in the Rockies helps. Yesterday it got up to a balmy 50 degrees.
I’ll keep you posted as things move along. i plan on building quite the farm.
That should be “living space” in quotes.
Which LTC exchanges would your recommend for trading LTC to BTC?
The only two that I’ve used are Vircurex and BTC-e; they’re the two largest at the moment (at least until Mt. Gox gets around to adding support for LTC). Be careful if you use others; there are some sketchy ones out there.
Question on 7950/7970, the power consumption looks similar abotu 253/258 under load conditions (reference: review sites). YOu get a better hashrate of about 10 – 15% for an albeit higher cost of 30 – 40%. But wouldnt this be better? Maybe a tweaking can squeeze out more juice?
The 7970 pulls about 30-40 watts more than the 7950 and gives hashrates of about 720 Kh/sec when run near its limit.
The 7950, if run near its limit will give hashrates of ~670 Kh/sec.
So the 7970 gets you about 7% more performance for ~20% more energy, plus the much higher upfront cost and a higher PSU requirement (this assumes that neither card is undervolted, but the ratios remain the same if you undervolt both cards similar degrees). Some people opt for the 7970, but I think the 7950 is a much better deal.
makes sense…The reason why i put that up because, i was going to opt for seasonic 1200…anyways..still researching…thanks for a wonderful / helpful post
Thanks for this excellent guide! I am in the process of building my first rig with the exact hardware you listed. I just had one question, do you think the SeaSonic Platinum-1000, http://www.newegg.com/Product/Product.aspx?Item=N82E16817151105, would be large enough to supply a rig with 4 of the msi 7950 cards you suggested? I would be undervolting the cards. I see the other ~1200 you mentioned is only a gold unit, but would like the most efficient I can get.
You’d probably be fine with the 1000w Seasonic if you’re undervolting, although you’d be cutting it pretty close. Even though the 1250w Seasonic is only gold rated (vs the platinum rating on the 860w and 1000w models), you’ll likely still use slightly less power with the 1250w.
PSUs are most generally most efficient at 50-80% load, and they tend to drop quite a bit when pushed to their maximum, which you’d be doing with 4 GPUs on a 1000w unit. For example, the 80 Plus certification wikipedia entry shows that a platinum-certified unit at 100% load may be slightly less efficient than a gold-certified one at 50% load.
The effective efficiency between the two units will likely be a wash after taking into account the load level you’d be running each at, so I’d personally be more comfortable going with the 1250w unit for 4 GPUs.
Thanks for the quick reply! Very good point. I think I will go ahead with the 1250w you recommended then. Looking forward to being able to buy you a LTC beer in the near future!
I am posting this question to the group in hopes of a more definitive answer.
I am planning on building quite a few rigs. I am looking at this as more than just a hobby. I live in an older house and want to use a separate room for my rigs. After looking at my circuit breakers, I realized that a rig as designed on this website would pull about 5.83 amps, and since the room I’m going to use is on a 20 amp circuit breaker, I would only be able to get 3 rigs in the room before having issues. Therefore, I called an electrician who arrived and said that he could install 240v outlets in the room, and then with the use of a UPS system he could step down the system to 120v allowing me to get quite a few rigs in the room. I was aiming for 30 as a goal and he surpassed this by saying we could get 32.
I should state that upgrading my power box is out of the question. I have 150amp service and could upgrade to 200amps but not 400amps. My electrician states an upgrade of the service is not necessary.
OK, so obviously, this is a major project, but pick up your jaw and here’s the rest pf the story.
I live in a place where the weather is very cool year round. i am not worried about heat issues because the high temp here during the summer is about 80* F. Right now, in May it’s about 50 or so. The 80* might last 6 weeks at the most, so keeping the rigs cool is not an issue. A few fans, maybe a window air conditioner for the hot months and we should be fine. I’ll cross that bridge when I get to it.
The problem is not the cooling but how to connect the rigs to the 240v and step them down to 120v.
My electrician suggested that I use a combined transformer/UPS system for the rigs. He has someone who I can buy these from but the cost is $5300 a piece…… And he said I would need FOUR of them…..Not cheap and I don’t think I need to spend that much money. However, his product would allow me to hook up 8 rigs each for a total of 32 and protect them with UPS (as we sometimes have high winds and storms here which can cause brown outs and black outs). His specification was a 7.2kw UPS system (4 of them) that would pull 96 amps at the wall (total all four) at 240v but deliver twice that at 120v.
It sounds like a great idea, but the cost is well out of my comfort zone. On the flip side (and something I do like) his system is portable so that allows me to move everything. Since I only plan on being here for 3 years, this is a good thing.
So I have made a few suggestions, such as why not just have a step down transformer without a UPS? They are much cheaper, will do the same job, and you can always hook up a separate UPS to them or just a realy good surge protector.
Something like this:
http://www.tripplite.com/en/products/model.cfm?txtModelID=4531
hooked up to something like this:
http://www.amazon.com/CyberPower-CP1500AVRLCD-Intelligent-1500VA-Mini-Tower/dp/B000FBK3QK/ref=sr_1_2?ie=UTF8&qid=1369241920&sr=8-2&keywords=UPS
or this
http://www.amazon.com/Monster-MP-AV-800-PowerCenter/dp/B00003CWDH/ref=sr_1_14?s=electronics&ie=UTF8&qid=1369242018&sr=1-14&keywords=surge+protector
Anyway, you get the idea. I could probably do this for about 75% less than what he was saying and still protect my rigs.
However, I have not been able to find a tripplite or anything similar in the same configuration as what my electrictian was suggesting. He said 7.2kw and the tripplite above is 6kw and the highest I have found.
Does anyone have a better suggestion? I plan on building my rigs one at a time, over several months, and I’ve thought this through pretty thoroughly. I just need some logistical help, so please just give good suggestions, not reasons why I shouldn’t proceed.
Thank you.
Good sir,
You needn’t make it so complicated. The psu choices discussed here operate great on 240v. It is crazy for your roi to design a farm of this scale all on ups. Use wire and outlets to 240v 20a or 30a spec. Buy plug adapters for your psu’s, use high amp surge protection if you are so inclined (you could do this at the panel or sub panel level). Keep in mind that nothing but pc psu’s can run off of these dedicated circuits. You will find that heat becomes a problem at a lower number of rigs than you expect, 6-8in centrifugal blowers intake and outtake through windows works a treat without ac if you live in an appropriate latitude which it seems you do.
Thank you for your help.
My understanding is that these would be 30a…4 or 5 of them depending on final configuration, and they would all be dedicated to the rigs alone.
However I am unclear about what you said about just plugging the PSU’s through an adapter. Wouldn’t I need a step down transformer to take 240v at about 100 amps to create 200 amps at 120v, so that I can run more rigs? What kind of an adapter are you suggesting? Can you get me a link to an example?
Cooling will not be an issue. I will figure something out, a fan sustem as you suggest.
It makes more sense electrically and economically to run the computer PSUs on 240v directly. As the PSU has an IEC C13 input and your outlets should be nema 6-30 if done to code, you will need an adapter cable to hook them up. Something like, http://www.powerfig.com/nema-l6-30p-to-iec-c13-250v-15a.aspx Make certain your PSUs accept 240v, almost all do, usually without any sort of switch. High wattage power supplies will be happier and operate more efficiently at 240v, and you will be able to run more rigs per circuit compared to the 120v option. Good luck on the project, you are on the right track. Most beginning miners just keep building rigs until the breaker flips, which doesn’t take much with these power sucking machines.
Thanks for the words o encouragement. I like your idea but I would need something more than a simple plug since my goal is to run 6-8 of my rigs off of one 240v outlet with a step down transformer. I understand where you are coming from so with your knowledge in mind, is there a 6-8 outlet extension cord of some kind where I could plug into 240v and then plug 6-8 rigs into “that”.
This is the main reason I was looking at a step down, in order to maximize my rigs and my understanding was that by using a transformer to go 240v to 120v I might use a total of 100amps at the wall but this would translate to 200amps available and thus more rigs and thus maximizing.
If there is a simple plug extension that would allow the same, you’d be saving me a ton of money. I’d even send you a few LTC if you have expertise to get me all the way there. 🙂
To be honest, the electrician wanted me to spend a ridiculous amount of money for UPS/Step Down units. He was talking $5300 a piece for 4 at over $20k, and when I told him no he hasn’t recontacted me yet, so I guess he was going for the upsell.
I am serious about getting very involved on mining here. I just need help with how to set up. It may take a while to complete the project and I still have to build my very first rig ever, but I have a vision and passion for this.
Thank you.
Like most things in life, with electricity, there is no free lunch. A transformer does exactly like it sounds, in this case it would transform 240v to 120v. What I think may be the confusion here is the amps component. 100a at 240v exactly equals the raw power of 200a at 120v. A component will draw nearly the same (there are conversion inefficiencies) number of watts whether on 120 or 240, however, the amps pulled will be halved when running on 240v. Watts = Amps x Voltage.
For rig density and efficiency, 240v wins every time.
As to your distribution requirements. You can get the job done for a good bit less than $20k 😉 You would get something like these http://www.amazon.com/dp/B0007YG85A , it has a nema 6-30 plug to connect to your newly wired 30a outlet. It has a bunch of iec 14 outputs to power your PSUs. Now you will need these cables to hook your PSUs to the PDU http://www.powerfig.com/iec-c14-to-c13-250v-15a.aspx
Just get your electrician (best to get a few quotes) to quote you for running 240v 30a breaker to nema 6-30 outlet with 10 gauge copper. These are double space breakers so there will be a limit to how many of these you can fit on a 200a residential service panel. (and still power the rest of the house, that is)
Thanks again Clippityclop,
I had to get a dictionary and use a wiki to understand a lot of what you said, but once I did, I understood it pretty well. This certainly saves a tremendous amount of money here. I can’t thank you enough. You sound like my goto guy for figuring this all out. I hope you don’t mind if I pick your brain from time to time on this.
With that in mind, I suspect that i could hook up a UPS to the Tripplite and then the rig to that as well. I don’t know if i have any other options, and I know you said these have circuit breakers, but I’m wondering with the way the brown outs happen here and blackouts if this wouldn’t be better. The reason I say this is because the UPS’s would allow me to program the rigs to shut down in an orderly fashion if the power was out for a period of time as the battery would allow that to happen with proper software for that purpose.
Or do you think this is overkill? I’m more worried about the brownouts and having a cleaner electrical feed to the rigs than just worrying about a power surge that would set off the breakers on the Tripplite.
Also I did see that Tripplite has a cooling system for “hard to get to places”…. http://www.amazon.com/Tripp-Lite-SRCOOL12K-Portable-Conditioner/dp/B002XITVCK
This might be worth looking into for the summer months even though it stays very cool here in the mountains.
Also, I really mean that i will help you out here. I have a few extra BTC (no LTC yet) in my wallet, and once I get this all set up with the bugs worked out, I’d be more than happy to pay you a consulting fee on all this, if you wouldn’t mind waiting until I get it set up with at least the first rig going. I just need someone who really knows his stuff and if I get stuck it would be great to have someone in my corner.
I’ll let you know when to send me your BTC address. Then I’ll know a proper rate of exchange for the help after all is said and done.
You could have everything on UPS, and dedicated AC keeping the room at 70f. But miners tend to be a cutthroat bunch and realize that fancy UPS system just cost you a profit for the year, or ever. I have been running rigs since mid 2011, no UPS, had a few power outages, everything has survived. You may live in an area with more line problems than average, maybe it makes sense for you. It would be a significant profit hurdle.
I really don’t know if litecoin will ever become BTC 2011-12 profitable on GPU rigs purchased today. Or even turn a profit once ASIC’s really penetrate BTC causing a final mass migration of GPU’s? Maybe? I hope so. Have some rigs khashing scrypt in the basement.
Air conditioning sucks power more than these mining rigs, I avoid it for all of but maybe three weeks a year.
We’ll play it by ear. I know that mining is a risk, but one I am willing to take. Thanks for the help and update. Now it’s all about building that first rig. I think you may be very correct about the UPS idea. Profits would be fairly thin at this point anyway, not like they were at the peak, but I’ll have to see. I’ll post if I have any more questions, and I’ll float you some BTC once the first set up is complete.
Just a quick question on the GPU choice here – I’ve found MSI 7950 single fan cards at a significantly lower price than the same cards with the Twin Frozr fans. Given that I plan to use the risers and crate option detailed in your guide, would it still be wise to pay the extra for the two fan option?
I don’t have any experience with the single-fan MSI 7950s. Even if you’re not able to use my exact settings, a realistic worst-case scenario is that you’d have to run them at stock clock speeds (eg: no overclocking or undervolting). You should still get at least ~570 Kh/sec out of virtually any 7950-based GPU, so if the up-front cost savings is significant, they might be a good choice. It’s also quite possible that they’ll perform nearly as well as the TF3 2-fan version that I recommend.
Hello CryptoB,
In some other comments you mentioned you can get around 1900 kH/s with exactly this setup.
I use 2 cards instead of 3, that should give met around 633 kH/s per card. However, I’m only getting 577 kH/s with each card.
Do you have any solutions for this? I’ve tried googleing but I couldnt find any useful information.
Greetz, Mustang3
Some more info:
Both cards steady at 70 degrees celcius
Both cards fan speed 2500 rpm
Got a monitor connected to the firt card and a dummy plug in the second
My internet speed is very fast.
The mining pool is located in the same country as I am (miningpool.nl)
I may have missed a step somewhere so I’m giving you an update on all this in an hour or so
Haha I asked too early, I found my problem and Im now running 640 kH/s each 😉
What was your problem if you don’t mind me asking?
I’m averaging 1800 kh/s but the numbers are progressively worse for each gpu.
For example:
GPU 0: 640 kh/s
GPU 1: 605 kh/s
GPU 2: 550 kh/s
Any help would be appreciated. Exact hardware as used in this guide.
Thanks
I put together a similar rig (different PSU – one 4GB DDR3 instead of 2 of 2GBs) as well for mining but with 2 cards at the moment (waiting for the third one to come back since it was RMAed).
I am also getting around 615-620Kh/s as well per GPU.
Settings are exactly the same posted here and to be precise here they are:
cgminer –scrypt -I 20 -g 1 -w 256 –thread-concurrency 21712 –gpu-engine 1050 –gpu-memclock 1400 –gpu-vddc 1.087 –gpu-fan 100 -o stratum+tcp://stratum.give-me-ltc.com:3333 -u “username” -p “password”
Do you see anything unusual?
Moreover one of the GPUs is getting HW errors (not a lot something like 30 per 24hrs) but they are there. Could it be defective as well?
Hardware errors should be really rare if everything is working properly. 30 in a day won’t impact your mining, but it’s possible that it is indicative of a potentially bigger issue. If you’re using risers, try connecting the card directly to the motherboard, and then try switching the PCI-E slot to see if the errors go away. If they don’t, I wouldn’t worry too much – the GPU will still mine perfectly fine for now, and if it does end up dying you have a 3 year warranty through MSI.
Your hashrate is on the low side of normal. You can try changing gpu-engine to 1070 and gpu-memclock to 1275. You should still be able to undervolt to 1081 mV at those settings but they might give you a bit more speed. If you get a sick or dead gpu message in cgminer drop the gpu-memclock by 5mhz until it goes away.
Continuation of the issues:
I clocked the GPU engine to 1070 and mem to 1275 however I was getting has rates below 600 so I clocked them to 1070/1420. Seems that I am getting around 630Khash from each one. Both cards are undervolted to 1.089 via MSI afterburner.
Regarding the HW errors now seem to be a more; around 150 for one of my GPUs. The other GPU is running just fine however a bit hotter.
Would these error affect mining?
What I am concerned about though is the performance.
I am having peaks and valleys in my stats provided by give-me-ltc. Hash rates drop below 1000 and sometimes go above 1300. Is this normal?
Also the average of WU (as far as I understand this is the important number) in cgminer is WU:1145.5/m.
Is this normal?
Seeing fluctuations in your estimated hashrate on the mining pool end is completely normal – they’re just giving a rough estimate based on the number of shares that you’ve submitted in the last x seconds. Your WU number is also fine.
The only item that I’d be mildly concerned with are the hardware errors. The number is low enough to not significantly impact your mining performance for now. If it continues to increase, or you see other issues on that GPU, you may want to consider RMAing it.
What up again Cryptobadger,
I have the GPU 3 rig all set up and am currently trying to add a 4th GPU. The issue is I dont want to go out and buy another PSU, as I have a few from stock desktops lying around. I have heard you could use 2 different power supplys on one rig. I have plugged both in (3 GPUs in the PSU from the guide and 1 GPU into this stock PSU i had) and the one by itself seems to run very fast and I fear it is getting to much power. I current do not have powered risers. how can I make this work?
Don’t do that without at least one powered riser! You’re risking frying your motherboard!
It’s ok to do what you’re doing as far as using two PSUs, but plugging in four 7950 GPUs into one motherboard without at least one powered riser is just asking for a fried board or worse. Each of those GPUs is still going to try to draw 75 watts through the motherboard, and that is likely way more than it was designed to deliver. It may appear to work fine for awhile, but it really isn’t safe.
Wait until you have at least one powered riser, and then you should be totally fine using two PSUs.
Maybe another FAQ.
Why does my average hash rate per GPU go down every time I add another?
For example: I am using Gigabyte 7970 ghz edition’s on MSI 990FXA-GD80v2
1 GPU = 770-780 kh/s x16 PCI-e on non-powered riser
2 GPU’s = 760-770 kh/s x16/x16 PCI-e on non-powered riser
3 GPU’s = 740-750 kh/s x16/x8/x8 PCI-e on non powered riser
4 GPU’s = 720-740 kh/s x16/x8/x8/x4 PCI-e with x4 on a powered riser
5 GPU’s = 700-720 kh/s x16/x8/x8/x4/x1 PCI-e with x4 & x1 on a powered riser.
NO OVERCLOCKING OR OVER/UNDER VOLTING. STOCK SPECS 1100/1500MHZ 1.256V
***FYI also have 8GB RAM, Sempron 145, running xubuntu with USB drive, and two 1200 watt corsair’s.***
Do you know why this happens? Is this normal?
Is it a cgminer issue?
RAM issue?
Voltage issue? Need all powered riser’s?
Thanks for your help
That is odd – I haven’t ever seen an issue like yours before, although I don’t have much experience with 7970s, which are notoriously tricky to get working properly. Your hardware setup looks fine to me. I googled a bit but wasn’t able to find anyone having an issue similar to yours.
Try posting about your issue over at the Bitcointalk forums. There are more than a few people over there running 4+ 7970 setups, and somebody should be able to help you.
I have quite a few un powered riser cables and was wondering which pins need the 12v power? and when the power is injected do the pins on the motherboard need to receive the power as well?
Not sure I understand your question. If you’re asking how to modify unpowered risers into powered risers, I haven’t done that myself, but there should be some guides on Google. You can also just buy powered risers directly.
Nice looking case btw!
This is the rig i am working on
https://docs.google.com/file/d/0B2VxsO5B0gmLcmZfMHRhVGdLdms/edit?usp=sharing
Hi Cryptobadger,what’s the proper command to get into the readme section of cgminer? I’m pursuing the idea of telling cgminer not to submit stales, is this a good idea or not?
I’ve read all of your tutorials and they are great. Unfortunately, I can’t apply them to LTC. This is why:
After much tweaking, I’ve finally managed to find that
–temp-target 78 –gpu-fan 33-100
are the best flags for me on cgminer for BTC or any SHA-256 based coin for that matter, but for LTC (or any other scrypt altcoin) it completely fails. I get 190 Mh/s when mining for BTC, which is right on the mark according to the mining hardware comparison chart, but when it comes to scrypt, I only get 1/10 of what the chart said I should get (I’m getting 20Kh/s). I tried using the flags on LTC’s chart too and also had no effect. Any light on this?
Thanks a lot for your work 🙂
Scrypt is somewhat more hardware intensive than SHA-256, so you’ll probably need to tweak your cgminer settings a bit from what you use for bitcoin mining. I’m not sure what hardware you have, but if you take a look at the bitcointalk forums, there is probably somebody with a similar setup to yours that can help you. Good luck!
Regarding GPU 4 and 5…
I have two rigs with the following PSUs:
* Corsair HX1050
* Corsair AX860
I’m assuming that the AX1200 you are recommending above would drive 5 GPUs with powered risers, and that I would be able to do 3 and 4 GPUs with my two PSUs above.
Please confirm!
Thanks!
Yes, a Corsair 860w will be fine for 3 GPUs, and a 1050w will be fine for 4, especially if you’re undervolting (if you’re not undervolting, you’ll be running pretty close to the limit and a 1200w unit might be better).
For 5 GPUs, the AX1200 will be enough if you’re undervolting (to at least the level I recommend in my Windows guide). If you’re not going to undervolt, then the most popular PSU for serious (5+ GPU) rigs is probably this one, which will handle five 7950s at stock voltages just fine.
Okay, so my goals are 5 GPUs/Rig.
From what I have learned so far it means:
1. I have to use Linux as Windows have trouble with more than 4 GPUs (Using Linux already)
2. I can’t easily undervolt on Linux
3. I need at least a 1250Watt PSU
4. Running PSUs close to max is not efficient.
SO… my conclusion is that the LEPA 1600 Watt PSU would be a better option than a the Seasonic SS-1250XM for about $30 more.
Risers, 6 gallon milk crates etc on its way…
Sounds about right?
BTW… any info on undervolting the MSIs on Linux? (I have cheap electricity but still this is nice to have!)
There are people on Bitcointalk running 6 GPUs on Windows just fine but yeah if you can find a LEPA 1600 for $30 more go for it. And let us know if you find out how to undervolt on Linux
Can you link to some info on 5+ GPUs on Windows?
Everything I read says 4 is the maximum.
I have a 1200 PSU with 4 GPUs. Undervolted I hover between 950 – 980. I could add a fifth GPU but only if I can undervolt!!
Yup, I’d go with the Lepa 1600w for five GPUs, especially if it is fairly close in price to the 1250w Seasonic.
Undervolting in Linux requires flashing a custom BIOS to your GPU. If you’re comfortable with a hex editor, you can make one yourself, or if you can find a trustworthy source online you can use somebody else’s (just make sure that they have the exact same GPU revision that you do). If you flash an incompatible BIOS to your GPU, there is an excellent chance that you’ll brick it, so make sure that you know what you’re doing! I wouldn’t try this at all on a GPU without dual BIOS (switch to the secondary BIOS to try flashing the custom ROM to, and switch back if it doesn’t work).
Got my 5 GPU rig up and running after some work and a failed PSU…
Tried to stay as close to the Part 1 of the rig with some small mods.
1. Using a 6 gallon milk crate.
2. The brace you recommended is not strong enough for the expanded span. It turned into a U pretty fast… I ended up with a covering a wooden stick with the brace.
Getting around 3.133 Mh/sec and consuming around 1500 Watts.
At 1500 Watts I’m really pushing what I should be having on a 15 amp circuit, so I need to get an electrician next, before expanding further.
This leads me to the question…
With the PSU supporting a range of Volts (115 – 240VAC) what is the optimal configuration for wiring/fuse boxes?
Yeah, my original braces are starting to sag a bit after many months of use in my first 3 GPU rigs. I’ve since switched over to using 1/2 inch PVC pipe to support the GPUs, which works perfectly and is just as cheap.
As for the electrical question, that is a bit outside my area of expertise. There are a few knowledgeable people that frequent the site though; hopefully one of them can chime in if they see this. An electrician should be able to provide advice, too.
Sorry, you’re gonna have to use the search over there. The question was really just that and there were a bunch of people saying they had a 5, 6, 7 GPUs installed on their Windows running just fine. Just try it 😉
I have a download cap of 100GB a month on my internet connection before it shuts off. You say you average around 30 kb/sec while mining. 30kb/sec doesn’t seem like much, but running 24/7 would add up. Is it still practical for me to mine?
Update: Sorry, I wrote this response too early in the morning. Everything I wrote below is based on 30 kiloBYTES per second, which is eight times more bandwidth than a typical rig will actually use. In my FAQ, I stated that my rig used 30 kb/sec – small “b” for kiloBITS. You should be totally fine running a mining rig (or multiple rigs) 24/7 even with a 100GB monthly cap. One rig running nonstop will use less than 10% of your monthly cap, even using a low-difficulty (and hence high traffic) mining pool.
It depends on what else you do online. Assuming 24/7 mining, a 30 kb/sec rig would use about 70% of your monthly limit. That leaves you 1GB a day, which is still a very large amount for most people. If you do a lot of video streaming (Netflix, etc), then you may hit your limit. Otherwise, you’ll probably be fine.
That 30 kb/sec estimate was also probably high – I measured using a pool where the difficulty was set to 32. You can get that number down significantly by using a high-difficulty mining pool, or one that uses vardiff. A higher difficulty ensures that back-and-forth communication is kept to a minimum. I’m currently using a vardiff pool (give-me-ltc.com) that keeps me at difficulty 128, which should in theory cut my bandwidth requirement down to less than 10 kb/sec.
Hi,
First of thank you for this great post. I have the same motherboard and I have 4 5970 and 1 5850. I run cgminer and have xubuntu 12.04. When I use 4 GUP’s [5970] everything runs fine. But when I plug in the 5th GPU everything breaks. I have tried using 1x to 16x riser cables for all GPU’s but still no luck. It seems like 4 GPU is the limit for this motherboard. Right now I user 2 x16 and 2 1x PCI-E slots.
Any suggestions on how I can make it use 5 GPU’s?
Thank you once again.
yl
When you say “everything breaks” when adding the 5th GPU, what specifically happens?
The computer boots up but xserver fails to start in case of Linux and in case of windows I get blue screen. In Linux I can ssh but the xserver won’t start.
Thank you
The windows bluescreen isn’t surprising – going beyond 4 GPUs in windows tends to cause all sorts of issues. You should be ok with 5 GPUs in linux, however.
Try this (with all 5 GPUs in your system):
Xorg -configureX -config /home/your linux username/xorg.conf.new
If that successfully starts X, replace the xorg.conf in /etc/X11/ with the xorg.conf.new that the above created in your home directory. Everything should work properly on reboot after that.
When I execute Xorg -configure I get the following error
Fatal server error:
Server is already active for display 0
If this server is no longer running, remove /tmp/.X0-lock
and start again.
Please consult the The X.Org Foundation support
at http://wiki.x.org
for help.
ddxSigGiveUp: Closing log
Hey Badger, this is some great stuff. I was wondering if you’ve had any luck getting this working over wifi and if you’d have any suggestions for me trying to get a setup like that done.
Thanks,
Do
I don’t recommend wifi if you can avoid it, but sometimes you don’t have the ability to run a wire. I actually have two miners running in my basement via wifi. But instead of putting a wireless adapter into each miner (you could absolutely go this route too), I just bought a cheap DD-WRT capable wireless router and set it up in bridge mode, and then placed it near my two miners. I then ran CAT5 cable from the bridged router to each miner.
If you’re going to be setting up multiple miners via wifi, then getting a cheap router and using it as a bridge is probably cheaper than putting a wireless NIC into each miner (I may do a quick tutorial on this at some point). If you only have a single miner, it’s probably easier to just install a wireless NIC and be done.
Got the AWUSO36H realtek for USD 25 and it’s working like a charm (fingers crossed) on xubuntu 13. Worked great on 12 too. Pretty much a breeze. For now, anyway.
Thanks.
Hi cripto badger, your guide is a live saver. Thank you very much for sharing it with all of us here. Got a quick question for now. I have no ability to get the internet installed at my place, and thinking of building a 6 GPU miner, is the mobile internet usb stick a solution? Does the mining eat a lot of data? Here in UK we have got a deal of 2gb per month for £10. Thank you in advance!
Bandwidth usage is minimal during mining; I posted the results of a short test that I ran in my FAQ.
In short, you should be able to run a miner full-time on 2GB of bandwidth without issues.
Newbie question here.
I’ve got everything up and running and am beginning to tweak my rig. Things seem fine, but I’m trying to set up my second pool and there are many option to choose from. I see that Badger has set himself up with a couple of the big pools and from what I see, it is advantageous because they have a higher probability of finding blocks, am I right?
The inherent danger, from what I understand, is that if a pool gets too large, it has becomes in danger of, well, basically, messing up the whole system.
If I’m going all for profit, however, shouldn’t I just try to sign up for the largest pool with the lowest charge?
Also, I am very curious about the P2Pool nodes. As I am entirely ignorant about this, it sounds like some more decentralized pool, and that idea appeals to me, even though their MH/s is low. Is there any advantage to sign up with one of them?
Thanks so much, Badger. Your website has been a huge help to me.
The concern over any particular pool getting too large is because of what’s known as a 51% attack. Basically, if any single entity can control more than half of the litecoin (or bitcoin, or whatever altcoin) network, they don’t have to play by the rules any more, and can cause all sorts of havoc. This is fairly easy to do with brand new altcoins, since the aggregate computing power of the new network is fairly low.
Litecoin is pretty well established now, so the amount of computing power necessary to accomplish an attack like this is enormous. Realistically, the only way it’d even be feasible is if the 3-4 largest pool operators got together and decided to cooperate in a coordinated attack. The amount of effort involved would still be substantial, and they’d probably stand to lose far more than they’d gain (they’d nearly certainly significantly devalue LTC, and being large pool operators, they likely have more to gain from seeing LTC succeed).
TLDR version: there probably isn’t any need to worry about a 51% attack on LTC. Pick whatever pool(s) seem reliable and fair to you.
As for P2Pool, I was never a fan because the LTC transaction fees can really eat into your profit. Instead of cashing out, say 10 LTC at a time – like you would at a typical push pool – with P2Pool you’re constantly “cashing out” a lot of tiny amounts of LTC. You get hit with the LTC transaction fee on each of these transactions and it can really add up. At least, that is my understanding, and I’ve never tried it myself. Transactions fees are lower now with the latest LTC client, as well.
Thanks.
Still thinking about it, but not too seriously. In the spirit of altcoins, it sounds like a good thing, but maybe there are some tweaks that need to be enabled.
Another unrelated question.
Seeing that cgminer can hit both ltc and ftc (and they vary in their profitability), has anyone been able to set up a way to actively check the value (worth) of switching between mining ltc and ftc without having to actively watch the worth of the mining operation and simply have the rig do all the work for you?
That sounds like it would be a great help in profitability and efficiency.
Regards.
Check out CryptoSwitcher, it’s exactly what you’re looking for. It’s a little complicated to set up, so you’ll probably want to Google for a tutorial.
Thanks.
Have you switched over to FTC mining (or others)?
I am wary because different sites are telling me different profitabilities, though they mostly say that mining FTC are more cost-effective/profitable.
I know:
http://coinchoose.com/
http://dustcoin.com/mining
http://www.coinwarz.com/cryptocurrency
These all say conflicting things, especially on the most profitable (perhaps) things. Dustcoin is saying that if I mine mincoin, I will make ~ 55 a week vs 27 on LTC and 28 on FTC. Coinwarz says that I’ll make less money mining mincoins. What gives?
Also, what would you all recommend to trade coins with? I’ve got ~ 10 ltc (yeah) and want to trade them for other currencies.
Coinwarz is nice for some info. I like the coins per day calculation for instance. The graphs are nice too. However it is not 100% reliable. Some coins look good on there but are duds when you try to mine them, or you can’t find a decent pool to mine them with. It also updates kind of slowly.
Coinchoose is a bit more accurate and is updated more quickly. However there are still duds and coins with inaccurate info. Plus on both sites, not all coins are represented. WDC is not on Coinchoose for instance, and it is a pretty good coin right now. (I think I read this is due to a technical problem with the coin). The best thing about Coinchoose is the graph at the bottom, if you can figure out how to turn each coin off and on.
The other thing about both of these sites, is that a coin can pop up to the top of the list for a very short while… usually when difficulty drops or the price goes up. It is important to remember this. The idea behind multi mining is to get in while the gettin is good and get out. Of course it is full of potential pitfalls, but could certainly be more profitable than just mining between LTC, FTC and/or WDC.
There are pools that multimine for you and also there are programs that can automatically point your rigs at pools you specify under certain conditions. Cryptoswitcher is one as mentioned. Multiminer looks a little easier to set up, but I don’t know how well it runs off a usb stick on a rig running Ubuntu. Right now I am just using multipools while I get my feet wet. I haven’t been at this very long.
As far as trading goes I like Cryptsy so far.
If you didn’t read this, you should. CB breaks it down pretty well about the alt coins.
http://www.cryptobadger.com/2013/05/altcoin-explosion-profit/
The profitability of altcoins can fluctuate quite a bit, day to day (or even hour to hour for new coins). Unless you plan to be really involved with trading to take advantage of short-term price fluctuations, I’d only pay attention to average profitability over a longer time frame (coinchoose.com will show you the average over the past 7 days). Litecoin is generally near the top when you look at longer periods of time, and it probably has the brightest future prospects among the various altcoins.