CGMiner only mines 1 card scrypt, 4 cards otherwise. Why?

[kjib]

I'm running CGMiner on Ubuntu 12.04 and with SHA-256 all 4 GPUs will be doing stuff. Clearly all 4 cards are seen by CGMiner. BUT, with scrypt mining CGMiner only appears to be doing stuff on 1 card. The other cards will all be showing 0Kh.

With the same set-up and a single card it runs fine and on that machine I have 4G ram, all as expected. On the other machine I have 4 cards so thought that 4x the RAM would do the trick, I have 16G ram so I assume that's not the issue.

The cards are all 7970s.

Here's what the script looks like for starting CGMiner:

Code:

export GPU_MAX_ALLOC_PERCENT=100

cgminer.exe -o stratum+tcp://POOL_URL:POOL_PORT  -u MY_MINER_NAME -p x --scrypt -I 13 --shaders 2048 --thread-concurrency 8192 --lookup-gap 2 -g 4 -w 256 --gpu-engine 1045 --gpu-memclock 1750 --auto-fan

What am I doing wrong

[iGotSpots]

My suggestion would be to stop trying to run 4 threads per GPU before you get everything stable

[Damnsammit]

My suggestion would be to stop trying to run 4 threads per GPU before you get everything stable

Right! 

Run everything at default and get them all working first.  Then play with thread concurrency, intensity, and the other stuff.

[Walt Sobchak]

My suggestion would be to stop trying to run 4 threads per GPU before you get everything stable

Right! 

Run everything at default and get them all working first.  Then play with thread concurrency, intensity, and the other stuff.

Dude, your picture dude.

[Damnsammit]

Fuck it man.  Let's go bowling.

My suggestion would be to stop trying to run 4 threads per GPU before you get everything stable

Right! 

Run everything at default and get them all working first.  Then play with thread concurrency, intensity, and the other stuff.

Dude, your picture dude.

[Walt Sobchak]

Fuck it man.  Let's go bowling.

My suggestion would be to stop trying to run 4 threads per GPU before you get everything stable

Right! 

Run everything at default and get them all working first.  Then play with thread concurrency, intensity, and the other stuff.

Dude, your picture dude.

"I told that fucking kraut down at the league office a thousand times I don't roll on shabbos"

"They already posted it walter"

"WELL THEY CAN FUCKIN' UNPOST IT!!!!!"

[Damnsammit]

Ahhh thread jack. 

What a great movie.

[User_513]

I'm running CGMiner on Ubuntu 12.04 and with SHA-256 all 4 GPUs will be doing stuff. Clearly all 4 cards are seen by CGMiner. BUT, with scrypt mining CGMiner only appears to be doing stuff on 1 card. The other cards will all be showing 0Kh.

With the same set-up and a single card it runs fine and on that machine I have 4G ram, all as expected. On the other machine I have 4 cards so thought that 4x the RAM would do the trick, I have 16G ram so I assume that's not the issue.

The cards are all 7970s.

Here's what the script looks like for starting CGMiner:

Code:

export GPU_MAX_ALLOC_PERCENT=100

cgminer.exe -o stratum+tcp://POOL_URL:POOL_PORT  -u MY_MINER_NAME -p x --scrypt -I 13 --shaders 2048 --thread-concurrency 8192 --lookup-gap 2 -g 4 -w 256 --gpu-engine 1045 --gpu-memclock 1750 --auto-fan

What am I doing wrong

Um, not using the 'search' function for the forum? https://bitcointalk.org/index.php?topic=117221.0

[Walt Sobchak]

Ahhh thread jack. 

What a great movie.

Indeed, I love it.

On a serious note to the OP try -g 1 DO IT NAO

[Walt Sobchak]

And maybe thread concurrency 22400

[kjib]

Indeed, great movie!

The problem is not one of stability, it runs fine but just on one of the cards while the other sit there doing jack all.

I will try the -g 1 ASAP.

Thanks for the link to the litecoin stuff. I did do a search & did not find the problem I'm seeing (but that thread is massive so I guess if it's anywhere it'll be in there. Thanks.

[iGotSpots]

Always start low and work your way up

[cannonfodder]

I'm running CGMiner on Ubuntu 12.04 and with SHA-256 all 4 GPUs will be doing stuff. Clearly all 4 cards are seen by CGMiner. BUT, with scrypt mining CGMiner only appears to be doing stuff on 1 card. The other cards will all be showing 0Kh.

With the same set-up and a single card it runs fine and on that machine I have 4G ram, all as expected. On the other machine I have 4 cards so thought that 4x the RAM would do the trick, I have 16G ram so I assume that's not the issue.

The cards are all 7970s.

Here's what the script looks like for starting CGMiner:

Code:

export GPU_MAX_ALLOC_PERCENT=100

cgminer.exe -o stratum+tcp://POOL_URL:POOL_PORT  -u MY_MINER_NAME -p x --scrypt -I 13 --shaders 2048 --thread-concurrency 8192 --lookup-gap 2 -g 4 -w 256 --gpu-engine 1045 --gpu-memclock 1750 --auto-fan

What am I doing wrong

Try doing your settings times 4, separated by a comma. For example, -I 13,13,13,13 --shaders 2048,2048,2048,2048 etc.....

[kjib]

OK, I changed

Code:

cgminer.exe -o stratum+tcp://POOL_URL:POOL_PORT  -u MY_MINER_NAME -p x --scrypt -I 13 --shaders 2048 --thread-concurrency 8192 --lookup-gap 2 -g 4 -w 64 --gpu-engine 1045 --gpu-memclock 1750 --auto-fan

To:

Code:

cgminer.exe -o stratum+tcp://POOL_URL:POOL_PORT  -u MY_MINER_NAME -p x --scrypt -I 13 --shaders 2048 --thread-concurrency 8192 --lookup-gap 0  -w 64 -g 1 --gpu-engine 1045 --gpu-memclock 1750 --auto-fan

(changed lookup-gap to 0 and -g to 1).

This worked "OK" on 3 cards but nothing on card 2. I didn't bother to check the # rate at this point.

To:

Code:

cgminer.exe -o stratum+tcp://POOL_URL:POOL_PORT  -u MY_MINER_NAME -p x --scrypt -I 13 --shaders 2048 --thread-concurrency 8192 --lookup-gap 0 -g 1 --gpu-engine 1045 --gpu-memclock 1750 --auto-fan

(Took out -w, changed lookup-gap to 0 and -g to 1).

Now all 4 cards work, "YAY"  but the # rate is so bad (200 to 400K per card) where I'd expect 600-700+

I do wonder if I'm coming up against a bus/memory bandwidth issue or something like that.

Anyone else nailed this?

[User_513]

Here's a couple of tips based on my observations and experience. Your mileage may vary. Limit one offer per customer. Batteries not included. Always ride safely and wear a helmet. Don't forget your towel.
 
- Dial in each card separately
- Use a *.conf file instead of the command line, it makes life a lot easier.
- Thread concurrency may differ for the same cards plugged directly into the MOBO vs plugged in with 1x-16x or 1x-1x risers, likewise for powered/unpowered risers.

Go forth, tweak, and you're welcome.

[Walt Sobchak]

OK, I changed

Code:

cgminer.exe -o stratum+tcp://POOL_URL:POOL_PORT  -u MY_MINER_NAME -p x --scrypt -I 13 --shaders 2048 --thread-concurrency 8192 --lookup-gap 2 -g 4 -w 64 --gpu-engine 1045 --gpu-memclock 1750 --auto-fan

To:

Code:

cgminer.exe -o stratum+tcp://POOL_URL:POOL_PORT  -u MY_MINER_NAME -p x --scrypt -I 13 --shaders 2048 --thread-concurrency 8192 --lookup-gap 0  -w 64 -g 1 --gpu-engine 1045 --gpu-memclock 1750 --auto-fan

(changed lookup-gap to 0 and -g to 1).

This worked "OK" on 3 cards but nothing on card 2. I didn't bother to check the # rate at this point.

To:

Code:

cgminer.exe -o stratum+tcp://POOL_URL:POOL_PORT  -u MY_MINER_NAME -p x --scrypt -I 13 --shaders 2048 --thread-concurrency 8192 --lookup-gap 0 -g 1 --gpu-engine 1045 --gpu-memclock 1750 --auto-fan

(Took out -w, changed lookup-gap to 0 and -g to 1).

Now all 4 cards work, "YAY"  but the # rate is so bad (200 to 400K per card) where I'd expect 600-700+

I do wonder if I'm coming up against a bus/memory bandwidth issue or something like that.

Anyone else nailed this?

Keep -w (worksize) to 256 for your cards. That will work best for 7 series. Have you checked some of the example configs on github? try taking any extra parameters out except for thread concurrency, worksize, and intensity. Also remember scrypt is very memory intensivr. Bandwidth is not an issur since the hashing os all calculational on the cards. Its good to have some thing like a .70 ratio of engine to memory speed. For example on my 7950s im getting about 650 kh/s per card with three of them. Im using an engine speed of 1100 and memory speed of 1500.

You have to add --gpu-engine (speed you want) and --gpu-memclock (speed you want) as a parameter. Give it a try, i bet it will work

[Walt Sobchak]

Sorry I butchered that last post. Phone keyboard...

[User_513]

Why do people continue to use the 'shaders' flag/variable when the 'thread-concurrency' flag/variable supersedes it?

[Walt Sobchak]

Example of something close to my config:

Cgminer.exe --scrypt -o stratum+tcp://POOL_ADDRESS:PORT -u username -p password --thread-concurrency 22400 --gpu-engine 1100 --gpu-memclock 1500 -I 19 -g 1 -w 256






Don't forget to add the --scrypt to the beginning like in my example! Let me know how my suggestions work out for you!

[Walt Sobchak]

Why do people continue to use the 'shaders' flag/variable when the 'thread-concurrency' flag/variable supersedes it?

No idea, it shouldn't be used at all