Another LiteCoin + CGMiner + 7950 mining thread.

[skeeterskeeter]

Yes, I have searched, tried, searched, and tried again to no avail.

I am trying to mine litecoins with my good ol 7950 on windows 7 with CGMiner and am having some issues.

So I first tried these arguments

Code:

F:\cgminer.exe --scrypt -o POOL -u USER -p PASS

This actually gets me up and mining but at a miserably slow rate, something along the lines of 15kHash. Also quick question before we proceed. On www.dustcoin.com it lists the Litecoin difficulty at 1014, why does CGMiner show it at 66.5M ?



So I then tried some other arguments, actually all of the arguments on https://litecoin.info/Mining_hardware_comparison none of which let me mine.
For instance this set of arguments

Code:

F:\cgminer.exe --scrypt -o POOL -u USER -p PASS --shaders 1792 -I 19 -w 256 --thread-concurrency 24000 -g 1

produces the same error I get with every other set of arguments I try



I know the shaders should be set to 1792 for a 7950 and the thread-concurrency should be 21712 or 2400. I cannot find any combination of arguments that produces above 20kHash. Am I missing an argument, do I have one set to something wrong? Could anyone suggest a simple set of arguments that work for a 7950?

In the end I want to run the GPU at a nice slow speed to keep the temp in my room down.

[Eli0t]

what happens when you remove --thread-concurrency 24000 and change -g 1 to -g 2

[aa]

You are missing a command before you run cgminer. Run it in a command prompt and it should tell you if it's set it successfully.

Code:

setx GPU_MAX_ALLOC_PERCENT 100

After that, just use this:

Code:

cgminer --scrypt -o POOL -u USER -p PASS -I 20 --thread-concurrency 24000

Keep in mind that this will make it so that your desktop is unusable. If you want to do anything other than mining, you'll have to lower intensity (-I) to about 15 or 14.

If that works, you can tweak thread-concurrency.

[balanghai]

Drop your TC to 8192 and see what happens.

[aa]

On www.dustcoin.com it lists the Litecoin difficulty at 1014, why does CGMiner show it at 66.5M?

cgminer difficulty = Litecoin difficulty * 65536

[skeeterskeeter]

You are missing a command before you run cgminer. Run it in a command prompt and it should tell you if it's set it successfully.

Code:

setx GPU_MAX_ALLOC_PERCENT 100

After that, just use this:

Code:

cgminer --scrypt -o POOL -u USER -p PASS -I 20 --thread-concurrency 24000

Keep in mind that this will make it so that your desktop is unusable. If you want to do anything other than mining, you'll have to lower intensity (-I) to about 15 or 14.

If that works, you can tweak thread-concurrency.

I took the first responses advice first and I used

Code:

F:\cgminer.exe --scrypt -o URL -u U -p P --shaders 1792 -I 12 -w 256 --thread-concurrency 8192 -g 1

Lowered the intensity and the thread-concurrency. Gets about 300kHash. Depending on the temperature over the next hour I might step up the intensity.

From the quote, what does the windows command do specifically?

Also, what is thread concurrency anyways? I'm in a CS degree and know of threads and concurrency, but what does the value mean? It doesn't really make sense in the terms I've learned.

[balanghai]

Usually the TC on the simple programs are simply instances or affinity for a certain application. But on the scrypt mining it means how much thread the cores will run in concurrency as the GPUs have lots of cores. And depending on your card, you can find a TC that will make your card run full speed but not bottlenecked just as what happened earlier with your 24k TC.

[skeeterskeeter]

Usually the TC on the simple programs are simply instances or affinity for a certain application. But on the scrypt mining it means how much thread the cores will run in concurrency as the GPUs have lots of cores. And depending on your card, you can find a TC that will make your card run full speed but not bottlenecked just as what happened earlier with your 24k TC.

So thread concurrency is the number of threads running on the GPU doing the scrypt algorithm?

[Melfice]

You have to install at least >3 GBs of RAM on your computer to mine with 7950. There is a bug in opencl that wont let you mine with all cards' available RAM (ie high Thread concurency >10000).
So try 4 gbs of ram in your pc and try again. Without it, try TC 8192.

[skeeterskeeter]

You have to install at least >3 GBs of RAM on your computer to mine with 7950. There is a bug in opencl that wont let you mine with all cards' available RAM (ie high Thread concurency >10000).
So try 4 gbs of ram in your pc and try again. Without it, try TC 8192.

I have 32GB of RAM.

[skeeterskeeter]

1. I set my intensity up from 12 to 14, and got 300+ HW errors very quickly.

2. I cannot change the thread concurrency at all from 8192 (64*128), I tried (64*256) and (64*192) with the same results as my first post.

3. I set -g to 2 instead of one, I got a little more speed. Nothing noticeable. In the README-scrypt in the CGMiner download, it says don't mess with it, but I did. What does it do? The readme doesn't really say much on it.

[vindimy]

Here's my .bat file for 7950 that's been giving me up to 650 MH/s mining Litecoin. Pretty stable.

Key difference: don't use "--shaders", use "--concurrent-threads" instead.

If this doesn't work for you, try lowering intensity and thread-concurrency until you get it right.

Code:

color 07
setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1
cgminer --scrypt^
 -o stratum+tcp://stratum2.wemineltc.com:3334 -u USERNAME -p PASSWORD^
 -o stratum+tcp://us.wemineltc.com:80 -u USERNAME -p PASSWORD^
 --intensity 18^
 --worksize 256 -g 1^
 --thread-concurrency 26816^
 --auto-fan --auto-gpu^
 --temp-target 79 --temp-overheat 84 --temp-cutoff 86^
 --gpu-powertune 0^
 --device 1^
 --no-submit-stale
pause

Make sure your case has a very good airflow. In the past all problems I had were resolved by adding more fans or making the fans spin faster.

[balanghai]

Usually the TC on the simple programs are simply instances or affinity for a certain application. But on the scrypt mining it means how much thread the cores will run in concurrency as the GPUs have lots of cores. And depending on your card, you can find a TC that will make your card run full speed but not bottlenecked just as what happened earlier with your 24k TC.

So thread concurrency is the number of threads running on the GPU doing the scrypt algorithm?

Yes that's right. And sometimes if your clock settings are in tune you could get higher hash rates with just adjusting the TC from there.

[aa]

You are missing a command before you run cgminer. Run it in a command prompt and it should tell you if it's set it successfully.

Code:

setx GPU_MAX_ALLOC_PERCENT 100

After that, just use this:

Code:

cgminer --scrypt -o POOL -u USER -p PASS -I 20 --thread-concurrency 24000

Keep in mind that this will make it so that your desktop is unusable. If you want to do anything other than mining, you'll have to lower intensity (-I) to about 15 or 14.

If that works, you can tweak thread-concurrency.

Did you bother to do any of this?

[skeeterskeeter]

You are missing a command before you run cgminer. Run it in a command prompt and it should tell you if it's set it successfully.

Code:

setx GPU_MAX_ALLOC_PERCENT 100

After that, just use this:

Code:

cgminer --scrypt -o POOL -u USER -p PASS -I 20 --thread-concurrency 24000

Keep in mind that this will make it so that your desktop is unusable. If you want to do anything other than mining, you'll have to lower intensity (-I) to about 15 or 14.

If that works, you can tweak thread-concurrency.

Did you bother to do any of this?

I will try it here soon and post results, I am going to try something like the .bat vindimy posted.

[skeeterskeeter]

Code:

setx GPU_MAX_ALLOC_PERCENT 100

Works beautifully to allow me to raise the thread concurrency to 22400 (350*64), added in auto fan and gpu just to sleep well and intensity at 13. About 300kHash and 74C temp.

Thanks everyone.

[aa]

Code:

setx GPU_MAX_ALLOC_PERCENT 100

Works beautifully to allow me to raise the thread concurrency to 22400 (350*64), added in auto fan and gpu just to sleep well and intensity at 13. About 300kHash and 74C temp.

Thanks everyone.

Read the following: http://www.lurkmore.com/wiki/Cgminer.conf

Follow the link at the bottom of the page for more in-depth information on what the flags all do.