2x 7970 crash

[scouzi]

I have 2 7970 (Gigabyte and Sapphire) setup. Individually, both cards can get 700+ MH/s.

When I run them together one is at 700Mh/s and the other at 540 Mh/s. Both are at 1180 clock rate. I noticed that the GPU on the slow card (Gigabyte) is capped at around 80%. I'm running on auto-intensity. When I try to boost the intensity of the slow card, the entire computer crashes! I need to unplug and reset the power button.

As stated, individually both cards are able to get 700+ Mh/s.

I'm using cgminer 2.11.4 with diablo kernel. Not much settings except clock memory set to 340 and --auto-gpu and --auto-fan.

Temps stabilise around 73% on both cards with one card at 80% GPU (Gigabyte) and the other 98% GPU (Sapphire).

Running on Windows 7 and monitor is attached to the slow card via DVI.


 

[cimpex]

crossfire bridge attached? don't use it!

[scouzi]

Thanks. I have no cross-fire attached or enabled (it's disabled in Engine control center). It's weird that the computer just stops (no blue screen). Seems to be thermal shutdown but I don't see any temps being radically high. It stops as soon as I press enter to change it in cgminer.

Maybe a PSU or Motherboard issue.

[GoldSeal]

get rid of that gigabyte card. gigabyte overvolts those cards. They frequently crash. I'm mining Sapphire 7970's only now. I burned up a gigabyte card in 3 hours last week and RMA'ed that POS.

hehe

[scouzi]

get rid of that gigabyte card. gigabyte overvolts those cards. They frequently crash. I'm mining Sapphire 7970's only now. I burned up a gigabyte card in 3 hours last week and RMA'ed that POS.

hehe

Both of my cards (Sapphire and Gigabyte) are running at voltages of 1.175. The only difference is memory voltage which is .1v lower on the Sapphire.

[GoldSeal]

It depends on the card model. Check out this thread on a litecoin forum:
http://forum.litecoin.net/index.php?topic=2115.0

[jgm_coin]

Thanks. I have no cross-fire attached or enabled (it's disabled in Engine control center). It's weird that the computer just stops (no blue screen). Seems to be thermal shutdown but I don't see any temps being radically high. It stops as soon as I press enter to change it in cgminer.

Maybe a PSU or Motherboard issue.

That actually happened to me this morning.  I think it was a combination of all my mining software getting the stability fracked up because after I shut off the CPU overclock testing, CPU scrypt miner and GUIminer, everything came back into work. 

Best,
jgm_coin

[scouzi]

Thanks. I have no cross-fire attached or enabled (it's disabled in Engine control center). It's weird that the computer just stops (no blue screen). Seems to be thermal shutdown but I don't see any temps being radically high. It stops as soon as I press enter to change it in cgminer.

Maybe a PSU or Motherboard issue.

That actually happened to me this morning.  I think it was a combination of all my mining software getting the stability fracked up because after I shut off the CPU overclock testing, CPU scrypt miner and GUIminer, everything came back into work. 

Best,
jgm_coin

With all the crashes my Win7 wouldn't boot up anymore (so I though but it was just really really slow)- and the disk was making a strange clicking noise. It turned out to be a corrupted user profile in WIN7. Deleted the user and full scanned the drive but I'm back in business.

I isolated the crash point at being aggressive on the Gigabyte GPU. When I increase the intensity to increase the load factor on GPU, the 2nd thread becomes active and crashes the whole rig. As stated, it's fine standalone with with multiple threads. Strange isn't it?

So one 5970 is mining 543 Mhs/s (one thread only)
ANd the other 700 Mhs/s (2 threads)

I'll try to power one of the cards with another supply,

[whitetoo]

I didnt know about the crossfire bridge either, removed mine and getting better hashes for less watts. Win, win thank you!

[MisterMelancholy]

I've got 2 Gigabytes 7970s, each running with 2 threads. They run super hot (so hot I have to leave a door open for them in Alaska), but are stable at 1180/110, each pulling just under 720Mh/s.

Try running the card at 1100Mhz core with the second thread active and work your way up.

[scouzi]

I've got 2 Gigabytes 7970s, each running with 2 threads. They run super hot (so hot I have to leave a door open for them in Alaska), but are stable at 1180/110, each pulling just under 720Mh/s.

Try running the card at 1100Mhz core with the second thread active and work your way up.

Thanks - it was the PSU - traded the CoolerMaster 725W for a Corsair TX750 and all is good.