Thanks for posting that up about the 7700. It got me to try out some more clock/mem combinations on it as well.

Why intensity 16? I found I had the best hash rate at 19. (bfgminer)

Using a clock of 975 and mem of 1500 I was able to get a solid 200 out of each of my cards. EDIT: the miner tends to crash within 15 minutes at this clock.


Now.. that said.. my 7950's are REALLY starting to confuse me.

So on one of my rigs, I reinstalled win7 yesterday, and before I was able to get 620 k/hash out of them... now I can barely get 550..

to make things even more confusing... another rig (7950 and a 7870)... the 7950 gets 650 khash..... with the exact same driver and clock settings.

makes no friggin sense..

BTC hash rate is still the same though, with 600 each @ 1150 mhz core.


EDIT/RESOLUTION: Seemed to be a kernel/driver issue. I imaged the OS drive, reinstalled windows... found out the hashrate was normal.... restored the image.. and I was back in business again.

I found out how to get 390k/hash from a 7870!!!

essentially you treat it JUST like tacotime did with his 7770's...

Why? a 7870 is almost exactly a "double" 7770... double the shaders, and double the memory bandwidth.

No matter what I tried before, I could never get above 320 khash.

Downclocking the core all the way to 920 while bumping memory up to 1360 did the trick along with intensity 19.

Funny thing is... raise the clock to 1000 and the mem to 1450... 310 khash....

LTC mining is truly an art...

Yes, I added the importance of core to memory clock ratios to the guide.  It seems like it holds true for the 5xxx and 6xxx too, but someone will have to test it more extensively.  I'm now getting 200+ kh/s out of a 7770 with intensity 20.  Maybe now we can pull 650+ kh/s out of 7970s.

Try a core of 950 MHz and a memory speed of 1525 MHz, you should pull over 400 kh/s I would think.

I have a 7950 getting 640 kh/s at 1050/1500.

I tried your suggestion and the khash did not appear to increase.

mining now with a 6970 and i'm getting 486 kh/s at 900/1375, but i'm also getting about 0.1% hardware rejects.  even if i lower the clock i still get them.  is this normal?  i tested the card with occt and it checks out okay, temps are in the 50s-60s.

Had to log out on one of my machines with 2x 6970 in it because the compiz was taking 100% of the cpus in it. Well after doing that and logging back in as an Ubuntu Classic no effects desktop I have seen only 1 HW in over a day. So I would say the compiz using all the cpu has a bit to do with it as well them cards had hundreds of HW before this change now as close as you get to none after.

So, has anyone with a 7970 tried 915 MHz for core and 1360 MHz for RAM, thread_concurrency = 21000?  I think with these setting you might be able to crank the aggression up to 18 or 19 and get some decent speeds, but someone will need to confirm.

Hey taco, think you could make a program to generate batch files like cgeasy so it can setup multiple cards in the batch?

I think the one item that seems to be overlooked in the guides is that far more ram is necessary to run LTC mining.

How much ram are you running on that machine for the 3 cards?