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 
Thanks for the Guide; Awesome stuff.
question: Im running a few hd 6590’s on a MOBO with an amd A10. When i was bitcoin mining, i could throw in the A10 for a small gain in hash, but this miner seems to crash shortly after startup if i dont turn the a10 gpu off.
anyone have an a10 working? if so, what are your settings.
Thanks in advance.
just an fyi.. i did get the a10 mining stable on one of two mobos @ i=12. hashrate sux tho @ 45kh …
Cgminer is no longer supporting gpu’s. Bfgminer said he probably going to drop them as well. I know we can install older versions but what are we to do with new gen cards that are not tweaked, supported properly… what are our options? If I knew how to code or knew someone I guess we could fork it.
I wouldn’t worry about it. The performance of cgminer in GPU mining hasn’t changed in over 6 months. Any of the older versions back to cgminer 2.11 or so provide essentially the same GPU mining functionality and performance that the latest versions do. Support is being dropped essentially because there is nothing else to do GPU-wise.
If anything changes in the future, I’m sure that somebody will pick up the code.
Cryptobadger which water cooling system do you recommend to get some extra kh/s? I just bought three Sapphire VAPOR-X AMD Radeon R9 280X 3GB GDDR5 2DVI/HDMI/ GPUs (760 kh/s) and also three of those Powercolor radeon 7590 GPU’s (650 kh/s) . so can I run Linux with those? (please forgive my Newbness!!!) ___Oh yeah.. u heard about that company building LTC ASICs… wut do u think… u gonna buy one? they start being delivered in mid 2014 so should I just wait for he ASIC’s and not bother with the GPU’s (parts have not arrived yet and I can return them still)
hey moct do you mind sharing your settings for your powercolour 7950’s? I’ve got a few of them but I’m not getting near 650 k/h/s… Thanks!
ps. i’m currently running linux, so maybe I can help you a bit with your settings too!
I’d be interested in your cgminer settings for the Powercolor as well. I’m currently running a pair of them and I can get them both to ~650kh/s but experience a driver crash after about 30 seconds with one card getting throttled down to about 100kh/s until reboot.
hello,
well done for your guide man, it is absolutely stunning. professional work indeed, helping the masses get on board. well done.
one question to you though, can i ask you how much litecoin you’ve been mining daily with that rig for the last 4 weeks ? (just daily average for last week october and first nov, 2nd week nov, and current 3rd week of nov) ?
thank you
Thanks for the compliment!
The rigs outlined in my guide have been producing about 1.5 LTC per day over the past week. Sometimes a bit more, sometimes a bit less given that I use a PPLNS pool, and there will always be some variance.
You can expect that number to drop quite a bit as the difficulty rises in the coming weeks, given all of the attention litecoin is now getting. Of course, given the rapid increase in price recently, that doesn’t necessarily mean you’ll make less profit.
Hi, I was wondering if you could share your thoughts on the differences between x1, x8, x16 PCIe slots. I know that the x16 is the typical slot for a GPU, but typically mobo’s only have 2. If I use a riser for x1 or x8, should they be powered risers or unpowered? The x8 and x16 look identical in size, any performance for mining? Thank you!
Hi PeerMedia,
this link explains it pretty well: http://www.computing.net/answers/hardware/pcie-x1-vs-pcie-x16/41848.html . As for powered vs non powered, go for powered. I’ve burnt 2 non powered extention cables. The surge when fans went into overdrive were more than the non powered cables could handle….replaced them with powered cables and haven’t had a problem since.
Thanks, ordered powered risers. Based on that link, x1 and x16 are a huge difference, but does it affect mining? Since I’m seeing x1 are very common, I’m assuming no?
Fantastic guide btw, very informative and clean!
I’m new to this game and thinking of building your rig. I noticed that on dustcoin digital coin are the most profitable to mine? How easy would it be to change the mining software to start mining them or other coins? Could it be done automatically?
Regards.
Any scrypt coin can be mined with this rig with just a tiny change in the “laucher” of cgminer, beware though of exchange rate/volatility/volume/mining quantity
Hey guys, it’s me, yet again…
Sorry for all the questions but better safe than sorry.
Can you use a PCI-E 1x, using a powered raiser?
Out of stock, but yes: http://www.amazon.com/Powered-Flexible-Extender-Bitcoin-Mining/dp/B00CQBCKPY/ref=sr_1_2?ie=UTF8&qid=1386299141&sr=8-2&keywords=1x+to+16x+powered+riser+cables
What are some good ways to access the internet (ie wired or wireless external router) and manage multiple mining rigs with cgminer?
This looks like a router that would work for me if I go the wired route:
Mikrotik – RouterBOARD 750 http://www.newegg.com/Product/Product.aspx?Item=9SIA1EA0V54778&nm_mc=KNC-GoogleMKP&cm_mmc=KNC-GoogleMKP-_-pla-_-Wireless+AP-_-9SIA1EA0V54778&ef_id=UnJ5bwAAAR-Zc2x2:20131206015311:s
This will be a real learning experience for me as I’ve never done much of this type of networking, and I’m having trouble finding a clear guide for multiple mining rigs.
Hi Tony,
I’ve used RouterOS before and it’s pretty cool and powerful depending on what your needs are. If you are fairly new to networking then you will have more options then you will probably know what to do with which might be scary at first. Out of the box you shouldn’t have a problem but if you start to feel the need to play with the configuration (QoS, etc.) you might get overwhelmed depending on your skill level.
A router with dd-wrt pre-installed might be a better bet. Price wise you are going to pay more, but it will be more user-friendly.
Yeah, I can see that the better question would have been DD-WRT or Tomato:) One reasons why getting started with ltc mining helps me is that I’m needing to do a few things with computer builds that I’ve never done before, and getting good with networking is one of them.
I have two rigs, and they are both wired into a wireless router (that has 2 ethernet outlets). For my next rig I might try a wireless usb adapter. As far as cgminer goes, each rig is running its own install of the application, which I start, stop and monitor from two separate terminal (or putty on windows) sessions on my laptop. I am using ssh to do this as the laptop is wirelessly connected to the router. Hope this helps.
That helps Benny. I’ll end up with 5 x 3gpu rigs that will be placed in different rooms to take advantage of the heat they put out. A couple of the rigs will be wireless.
I was thinking a little fancifully about cgminer seeing all the gpus from all the rigs in one terminal, but I don’t have the skills to program something like that right now, and it’s probably not worth the effort.
Given that the real cards are now very hard to obtain without paying silly money do you have settings for the second best cards, the Radeon R9 280X cards.
Thanks for a truly excellent series of articles, these are the only reason that I am even contemplating getting into Mining!
Hi there,
I must say, yes wonderful Facts!! I have a question for you and I hope you can answer this. I’m trying to buy 3 Sapphire Radeon HD 5870 I’m just wondering if this a good start. I am more than like to pick them up for 200 to 300 bucks for 3 used ones. Please let me know what you think. I am trying to go under 1000 bucks for my rig when I build them. Please and thank you.
Thanks for the guide! My 3 R9 280x rig is running stable but my 4 R9 290s rig keeps showing mh/s instead of kh/s. I did put –scrypt in .bat file. Does that mean I’m mining BTC instead of LTC? Can anyone tell me how to fix it? Thanks!
Hello,
can you tell me you hashrate on you 290 build? and if you have unlocked your cards or not? 🙂
The problem is all fixed now. My cards aren’t unlocked. It gets on avg. 800 kh/s per card and avg. 3.15 mh/s for all 4 running. I’m still trying to see if I can get ~850 kh/s per.
hi
really nice guide 🙂
love it and easy to follow
got one question tho. is it easy to chance pool using putty?
if i would like to farm diffrent coin and would like to switch it really often.
Hi. I’m mining litecoins with a pair of XFX 7970’s under cgminer in Windows. I am using Catalyst 13.9 with the SDK that comes with it. I did not install a separate SDK. These are my cgminer settings:
cgminer.exe –scrypt %* –thread-concurrency 8192 -I 13 -g 1 -w 256 –lookup-gap 2 –gpu-engine 930 –gpu-memclock 1500 –temp-cutoff 90
%* is replaced by the pool address, user, and password. I don’t see much difference between engine clock being 930 vs 1050. I have also tried thread concurrency of 22392 and 24576. Again, not much difference.
Anyway, cgminer is showing the following after running for about a day:
cgminer version 3.7.2 – Started: [2013-12-09 01:38:18]
——————————————————————————–
(5s):1.998M (avg):945.2Kh/s | A:947424 R:5632 HW:0 WU:856.1/m
ST: 2 SS: 0 NB: 513 LW: 6294 GF: 5 RF: 0
Connected to mining.usa.dallas.hypernova.pw diff 128 with stratum
Block: 85203154… Diff:2.69K Started: [20:12:01] Best share: 6.13M
——————————————————————————–
[P]ool management [G]PU management [S]ettings [D]isplay options [Q]uit
GPU 0: 76.0C 2425RPM | 999.7K/472.9Kh/s | A:478048 R:2848 HW:0 WU: 430.4/m I:13
GPU 1: 74.0C 2563RPM | 997.6K/472.4Kh/s | A:469504 R:2784 HW:0 WU: 425.8/m I:13
——————————————————————————–
Apparently each card is doing about 1Mh/s (5s average) at any given time. Sometimes this dips down to about 800 or so and then comes back up. I’m not sure I believe these numbers.
What’s up with the overall averages though? Why are they so low? The pool I am mining at (hypernova) is showing a total of about 1.0Mh/s or so. This seems to confirm the average in cgminer, more or less. The pool estimate seems to range between 850Kh/s and 1.25Mh/s.
What might be causing this? Am I doing something wrong? Thanks.
Well, I solved my problem. The strange behavior was due to my computer’s clock being slow. Apparently it was running at about 50%. The 1Mh/s wasn’t real because it was about more like 1Mh/2s or 500Kh/s. And when my computer synchronized with an online time service, it cut my overall average in half. It makes sense now.
I updated my motherboard’s bios to the latest version and all of that went away. Then it showed my real hash rate… about 450Kh/s. 🙁
So I went digging and found a BIOS for a different 7970 and flashed that to both cards. Now both of them are doing 715-730 for a total of almost 1.5Mh/s. The pool reflects this now too, showing 1.71Mh/s currently. Yay.
If only I had figured this out a few days ago, I would have gained probably another litecoin by now. Unfortunately the difficulty is skyrocketing.
Hi Greg F,
i’d be really interested to find the new bios you found, as I have a small rig of 2 XFX’s runnung around 470KHs.
Can you point me in the right direction?
cheers
Hi Greg. I have his 7970 only running at 500 kh/s how did you update the BIOS mate? Im frightened to do anything now it’s all working after many frustrating days!
Would appreciate and advice and thanks.
Am I missing something here but why aren’t we all mining digital coin? Their the most profitable coin out there? Must be a reason.
Probably due to stability. Being a fairly new coin, it may be extremely volatile. It might go to 0 tomorrow. But litecoin and bitcoin aren’t immune to that either. Also if everyone started mining digital coin, it wouldn’t be profitable anymore.
Looks like I am wrong about the novelty. I guess I should do more research. The second point still stands though!
Wrong about the novelty? I thought the whole idea was to mine these coins and sell off at the current market rate so even if that coin is volatile and is dumped you can just switch to the next most profitable coin? That was my thinking, maybe a bit simplistic!
I meant I was wrong about how new it was. It is several months old at this point, which is a long time in altcoin world. It is also not all that profitable. According to http://www.coinwarz.com, it is less profitable than litecoin right now. With that said, I solo-mined it last night and got two blocks worth 30 DGC total by morning, or about $8. Not bad I guess. The difficulty has gone up quite a lot even since then.
Realistically, how can the market support that? Pump and dump only works short-term and kills the market at the same time.
Why would you dump it if you dont expect it to crash? Why would buyers repeat the same mistake of buying high?
Why is it that hashrate shown on cgminer is significantly different from hashrate shown on pool?
The hash rate on the pool is an estimate based on the number of shares generated. It is generally accurate to within +/-20%. The hash rate shown in the cgminer terminal window is what your cards are doing.
Cryptobadger thank you so much for these guides they were a huge help on setting up my first rig!
unfortunately i cant seem to find a fix for this error,
getting “Error -5: Enqueueing kernel onto command queue.
in GUIminer it shows as a connection problem and on CGminer i get about 8xx Khash with your FAQ batch file but no WU or accepted shares
I am running 2 R9 290s on 4gb Ram windows 7 64bit
13.11 catalyst
SDK 2.9
ive spent HOURS trying to figure it out plz help
Hello all,
I have a setup with 2 x 2GB Powercolor 7850s (I have a 3rd but it wont fit, waiting on a riser), 8GB RAM, AMD 6 core 3.5Ghz and running xubuntu on a 16GB USB stick. They have been averaging about 600 KH/s on cgminer. cgminer has been running smoothly with no hardware errors. For the first couple of days everything was going good and I was getting shares and LTC was hitting my account. Now, for quite some time the pool is showing a hash rate of 0 (I know that this doesn’t quite matter), my valid unpaid pool shares stay at 0, my account balance does not move and on my worker under the Active spot there is a “N”. Below are my cgminer settings, without my actual username and password.
#!/bin/sh
export DISPLAY=:0
export GPU_MAX_ALLOC_PERCENT=100
export GPU_USE_SYNC_OBJECTS=1
cd /home/YOUR_XUBUNTU_USERNAME/cgminer-3.7.2-x86_64-built
./cgminer –scrypt -I 19 –thread-concurrency 21712 -o stratum+tcp://usa.wemineltc.com:3334 -u USERNAME -p PASSWORD
cgminer is running fine, so I’m guessing this is an error on the pool’s side. Does anyone know what I need to do to fix this? It is very strange, everything was working great and without changing anything the above issues started. Also, does anyone know if there are better settings to run the 7850s at? I would like to get at least 350 KH/s out of each card, now I’m averaging 300 each. Thanks in advance everyone!
Below are links to a screen shot to cgminer.
http://tinypic.com/r/eimsl5/5
http://i44.tinypic.com/eimsl5.jpg
I have contacted the pool and they said they checked the server and everything is just fine.
About an hour ago I started wemineltc’s java client here at work and used the same worker and I have seen 1 valid unpaid share that did in fact increment into the paid shares. So maybe its not the pool?
Not sure when you took that screenshot, but the cgminer activity log shows that the last time you accepted a share was almost 3 days ago. You probably just need to restart cgminer.
Restarted the rig and everything is going smoothly now, thanks a lot!
Try using the world server on wemineltc; ive had problems with the usa server and switched to the world and they went away.
Hey would you mind sharing your settings for the XFX R9 280X. I have three, but have only used one so far. The best I can get out of mine is 610 kh/s. I’m running under linux with the latest catalyst from the repository. I’ve spent days trying to tune this thing (using the method outlined in SCRYPT README). Thinking about sending them back and trying to find another brand.
I have six of those cards, three per rig. They have to be the Black OC Edition.
I am running Xubuntu 13.10, Cgminer 3.7.2, and Cryptobadger’s hardware setup apart from the GPUs. I bought the recommended Seasonic 1250W gold PSU.
My settings actually vary between otherwise identical rigs, which is weird. On one rig I am getting stable 730KH/s and the other, 710, which is still preferable to 610KH/s.
My settings on the fastest one: –thread-concurrency 8192 –temp-target 70 –auto-fan –gpu-engine 1060 –mem-clock 1500.
The slower one –thread-concurrency 8193 –temp-target 73 –auto-fan –gpu-engine 1020 –mem-clock 1500
They are in a rather hot (and thanks to the rigs themselves, ever hotter) room with 13′ ceilings in a Western Sydney summer (about 30-37C outside). I have small 15 cm desk fans pointing at each, alighted longitudinally with the GPUs to maximise cooling.
I hope this helps.
Typos: aligned not alighted and two dashes before each setting but are not rendered in these blog posts.
Awesome guide Cryptobadger. I couldn’t have set anything up without your guide. Rather than try to add GPUs, powered risers etc, I am setting up a second worker with another 3 GPU to sit behind the first, with the seasonics sitting beside them. With diff at 3000+ and recent Chinese BTC/LTC market crash, I thought I’d bump up the mining a bit.
I am using XFX 280x black edition, with 710KH/s stable on each card. Three more in the mail. All other brands of 280X sold out in Australia and 290/290x are over $600 each here. I read bad reviews of XFX but that must have been the non-black (non-overclocked) edition, as I am getting consistent rates above 700.
While I am waiting for my riser cables to arrive, I have two of my GPUs running directly on the Motherboard. I can’t see that there is room for the third. They’re pretty thick; maybe that is just the width of the shroud on the XFX.
Curiously, one card runs at 78-80C and the other at 68-70C, but both at same hash rate. I have a box fan noisily ventilating them. When I switch that off, temp goes up by 3-4 deg within minutes. Could it be that the temp-target=70 (in your initial 280x testing settings)only applies to one card, since I entered those settings when I only had one card running (to set it up)? Surely I don’t have to enter settings for each card, or do I?
Thanks again for your excellent guide.
I might be wrong but if you have the cards in the same rig they will be at different temps due to the fact that the first card will be sucking in clean air but the second and third card will be sucking in warmer air from the card next to it. If you get me!
My cards temp are 68,72,74
And the first card is dumping it’s warm air across the next and so on….
[…] Update: Cgminer 3.7.2 is the last version to support scrypt—do not use any version after that! In addition, depending on which version you choose to use, you may receive an error complaining about libudev.so.1 when you try to run cgminer—you can find the fix for that here. […]
Cgminer is STILL complaining about a missing shared library file: libudev.so.1. after trying both fix options it says –
ln: failed to create symbolic link `/lib/x86_64-linux-gnu/libudev.so.1′: File exists
I’m running 3 powercolor AX7950’s
Anyone know of another solution?….cryptobadger, are you out there?
please help! Thank you!
If the file exists, cgminer shouldn’t be complaining about it missing – are you sure it’s complaining about libudev.so.1? A few people have seen it complain about libudev.so.0 – double-check the error message. If it’s the latter, try this:
sudo ln -s /lib/x86_64-linux-gnu/libudev.so.1 /lib/x86_64-linux-gnu/libudev.so.0Tried “sudo ln -s /lib/x86_64-linux-gnu/libudev.so.1 /lib/x86_64-linux-gnu/libudev.so.0” – you suggested and received this error “ln: failed to create symbolic link `/lib/x86_64-linux-gnu/libudev.so.0′: File exists”. Any help is greatly appreciated.
Hey miners in the UK
How are you selling your coins?
I’m trying to work out the best way to sell litecoins, convert them to bitcoins and sell on bitbargain? Any advice appreciated?
Phil
Phil,
I am also in the UK.
If you want to sell your LTC for £ sterling, I will take some off you.
Send me an email showing how many you want to offload.
Hi Joan
Thanks for the offer but I think I will keep them for now and see how value goes.
PS I dont really want to give out my e-mail address on here!
Thanks
Sure Phil, I understand.
I didn’t post my email address either.
The offer is still there though, for the time being, ( while I still have some spare cash that is, that is not earning any interest in the bank anyway)
rgds,
Joan
Hi,
I used your instructions to setup Ubuntu with a Club Radeon HD 7950. It all works fine, thanks for that. In Windows I used Guiminer-scrypt and with that it was possible to change quickly between different pools, and even different coins. Is there a way to do this with Ubuntu?
Ruud, You can direct cgminer to a pool, or switch to a different pool, by changing the pool address in the scrypt command line in “mine_litecoins.sh”, and then re-launching cgminer with “./miner_launcher.sh”. You don’t have to specify a coin, cgminer will mine whatever scrypt coin is being mined by the pool you are in. I switch pools frequently with no problems. When you want to change pools, go into your cgm screen, hit “Q” on your keyboard to stop the miner, when you are back in the command line use “nano mine_litecoins.sh” to get into it, then substitute the new pool address, save changes and exit, then resart cgminer with miner launcher. Good Luck
How many coins do you guys mine per day? I’ve followed this guide and I have a total hashrate of 1.8M and at hypernova.pw I get only 0.54 coins/day. Is this normal for you as well or can a pool make such big different (when this guide was written it’s said that you can expect 1 -1,5 coins per day, but I figure the difficulty has risen since then)?
Don’t expect to get rich doing this!
I’m at 11K KH/sec and making about 3 LTC/day. I was lucky and got in earlier in the process… I was making 10+ LTC/day before the prices skyrocketed using less hardware!
You all have to realize how this works. There is a fixed pie. (e.g. fixed number of coins being released by unit of time). The more people get into mining, the smaller piece of the pie each will get, and the faster the difficulty rate will increase. People are joining like crazy, and existing miners are expanding their capacity.
The process of smaller pieces are only expedited by the current big delta between cost of mining (e.g. electricity and HW purchase cost) and profitability.
Use this link to figure out what your investment will be worth when the difficulty goes up: http://bitcoinwisdom.com/litecoin/difficulty
Also, think about what to do if the price drops to the point where cost of mining is larger than profitability. It will happen at some point unless you don’t pay for electricity.
Hi, Thanx for the great information.
I built a 5 gpu mining with the MSI 77A
and 5 cards of 7950
I have a problem:
It worked for a while but now, every time i open the wallet and the CG watcher (i use cgminer 3.7.0) the mining starts but after a while, between 5-50 min the computer make a self restart. what is the problem?
Moreover, it’s seems that somthing eats my storage (the computer is just for mining) what shall it be?
{{i’m doing solo mining}}
That could be related to heat issues and/or power supply issues. 5 GPU’s are bound to use a lot of power and generate a lot of heat. Overheat protection might be causing restarts, maybe. Power supply issues are more likely to cause such problems, though, I would think. What kind of power supply do you have?
As far as storage being consumed, who knows. Try to figure out what is taking up all that space. I doubt it has anything to do with mining. That sounds more like a general computer problem.
Hi, thanx for your answer
My psu is LEPA 1600
I Built the computer with MSI Z77A-GD65 as instructed in
http://www.coinminingrigs.com/how-to-build-a-6-gpu-mining-rig
(I succeeded just with 5 gpu from the 6 optional.)
i’m runnig win 8
using Cg-miner 3.7.0 and CGwatcher 1.3.3.2
Now i moved the computer and checked all connections that seems OK. the computer now runnig for 18 hours and didn’t crush.
I can’t recognize what was the problem (it happened several times)
Now I have got a new issue:
one of the 5 gpu runs at 330 Mh/s (M)
while the others runs at 440 Kh/s (K)
I’m confused. it didn’t make sense.
any suggestions?
Thanks!
You probably have cgminer running in normal mode (SHA-256) on that GPU. Make sure all of them have the -scrypt option set in cgminer.
Also, if you are not using powered risers, you could be putting a lot of stress on your motherboard and its power circuitry.
Hi again,
I’m using Risers 1x to 16x as was instructed in
http://www.coinminingrigs.com/how-to-build-a-6-gpu-mining-rig
(when they published the 6 GPU MSI BOARD)
If you have any other ideas i will be glad to try.
Thanks a lot!
I’m sure I read on here that it’s better to go with a small pool than one of the larger ones but I can’t find where I read that so I’m posting in FAQ’s in the hope someone can tell me why this is?
Before I found this site I setup an account with WeMineLTC.com (34,901 workers as of this writing). Would it be beneficial to join a smaller pool? And if so, why?
P.S. I haven’t started ‘properly’ mining yet – still waiting for my 7950’s from Amazon.fr
Cheers.
Hi Guys,
I’m getting ‘Mode Not Supported’
H:75.4khz V:60.3hz
on my screen after I’ve installed the graphics drivers. Is this more likely to be a monitor issue as it’s quite old, or a software issue and I’ve made a mistake somewhere? Thanks.
Assuming it’s Windows, press F8 (repeatedly) before the Windows logo shows up on boot. Select the low-resolution 640×480 VGA mode option. That should allow you to reconfigure your graphics driver for the monitor you have.
Hi Greg. No it’s Linux. I should have specified. Don’t suppose you know how to get the same results?
That will probably require digging into the X server configuration file or using Xconfigurator. Possibly the driver has its own configuration utility. I haven’t messed with that stuff in a long time and therefore would not be much help.