HD 6990 trouble - only one gpu works

[freeminer]

Need help!

I recently bought new Gigabyte HD 6990 and find out that second of GPUs dont work properly. DiabloMiner show error: "ERROR: Invalid block found on Cayman (#2), possible driver or hardware issue". poclbm dont want to work with second gpu too. It begins to calculate, shows 350 Mhash/s and then says that "verification failed". I'm running on windows XP now.

Is this trouble a standard issue for HD 6990 or not?

Catalyst Control Center shows that second GPU is disabled and I didn't find how to enable it. 

[clonedone]

Which cata do u have 11.3? or 11.4?
can u switch to windows 7?

[MemoryDealers]

I'm having the same issue on my XP box

Any luck?

[clonedone]

well i just set up a brand new comp with two 6990 and windows 7 would not recognize both of them until i crossfired

try that out. try out crossfire first. then if not, try windows 7 if its not too much of a problem

[freeminer]

Which cata do u have 11.3? or 11.4?
can u switch to windows 7?

Hi!

I'll try it in the next few days.

[gat3way]

On linux you should disable crossfire and use Catalyst 11.4/SDK2.4. It works.

[freeminer]

well i just set up a brand new comp with two 6990 and windows 7 would not recognize both of them until i crossfired

try that out. try out crossfire first. then if not, try windows 7 if its not too much of a problem

I have only one hd 6990. HD6990 has two GPUs. First one (Cayman 1) works fine but with second one I got errors and CCC shows that it "Disabled"

[freeminer]

I'm having the same issue on my XP box

Any luck?

I find out that gpu-z recognize second gpu and poclbm can use it for a while. I mean that I started mining on second gpu and gpu-z shows loading increase on second gpu. And more interesting that I tried to do it several times and sometimes it worked within 2-3 minutes with no errors. I'll try other motherboard and windows 7 and report on the results

[clonedone]

I'm having the same issue on my XP box

Any luck?

I find out that gpu-z recognize second gpu and poclbm can use it for a while. I mean that I started mining on second gpu and gpu-z shows loading increase on second gpu. And more interesting that I tried to do it several times and sometimes it worked within 2-3 minutes with no errors. I'll try other motherboard and windows 7 and report on the results

what cata version?
on the windows 7 one be sure to download cata 11.4

[netxshare]

well i just set up a brand new comp with two 6990 and windows 7 would not recognize both of them until i crossfired

try that out. try out crossfire first. then if not, try windows 7 if its not too much of a problem

In windows you must use a dummy vga ( http://www.techpowerup.com/forums/showthread.php?t=86507 ) to get two 5970s or 6990s working.
This is what I have been told. Windows will shutoff the card unless it's setup under crossfire.

[freeminer]

I'll try other motherboard and windows 7 and report on the results

Hi!

With windows 7 all works fine on the same motherboard. I've installed special windows7 drivers for hd6990. Sorry for late reply.