Same GPUs, 250 difference in hashrate...

[chiznitz]

Hey all.

First of all thanks for the plethora of information that is already here.  I've done some searching and can't find exactly what I'm looking for.  if it's already been asked I'm sorry and please point me to the right location.

I just purchased a 2nd gpu for mining machine.  Here are my specs.

AMD FX 8350 Overclocked to 5ghz currently
Sabertooth 990fx r2.0 mobo
2x AMD HIS IceQ 280x
1000 Watt EVGA Platinum PSU
Windows 7 Professional

One of my cards hashes @ 740, the other is only hashing at 500.

Temps are almost the same (54,53).

Here is my cgminer 3.7.2 cmd line.

setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 0
cgminer --scrypt -o stratum+tcp://blah.blah:3333 -u workername.1 -p x -I 13 -g 2 -w 256 --thread-concurrency 8192 --gpu-engine 1080 --gpu-memclock 1500 --gpu-fan 70

I've also tried sync objects set @ 1 and 2 with no difference.

The only difference I can see in hwinfo64 for the cards is the following.

GPU0: GPU VRM Power Out (POUT) 183.75W
GPU1: GPU VRM Power Out (POUT) 125.75W

There are also some AMP's that are lower on 2nd card.


Also, I've tried this unoverclocked as well with same results.

Thanks in advance!

[1713887481]

1713887481

[meowmix4jo]

Try doing the settings for each card individually. I have two identical cards as well but they don't like the same settings. I have to run one with a slightly faster clock than stock, and the other much lower than stock for them to get around the same h/s. The difference isn't as big as yours (only ~100kh/s) but I'd check it.