Verification failed, check hardware!

[antz123]

Hey all, just finished setting up a dedicated rig, but having a few problems...

For some reason when using poclbm I'm getting this Verification failed, check hardware message on one of my cards. This only happens if I run both of my cards at once.

When using diabloMiner, it is happy to run both miners on both cards but one of them ends up mining at a rate of about 5mhash

What do you think could be causing the problem? Specs:

AMD Sempron 140
2 x 6950
Windows XP 32 bit
running catalyst 11.5 (crossfire enabled)

Thanks in advance! 

[benjamindees]

Power supply?

[antz123]

600W OCZ psu, more than enough for the system. I ran furmark for a while too... it didn't have any problems and ran both cards fine.

[Littleshop]

600W OCZ psu, more than enough for the system. I ran furmark for a while too... it didn't have any problems and ran both cards fine.

Seems a little close to me.  I would think you would want 700w for two video cards.

[willaien]

running catalyst 11.5 (crossfire enabled)

Disable crossfire and try again.

[benjamindees]

I would open up the PS and check for bad caps.  Only if you're comfortable with that sort of thing, of course.

[Basiley]

600W OCZ psu, more than enough for the system. I ran furmark for a while too... it didn't have any problems and ran both cards fine.

what 12V caps had that "600W" PSU ?
in Amps.

[picollo7]

I am having this same problem too.  It's not the PSU.

4850
750 W PSU
win7 32 bit
using 2.1

works anywhere from 5 - 30 minutes and then says Verification failed check hardware.

Tried with poclbm from 4/28 and 3/25.

the -v flag does not help.

Very frustrating and I know many other are experiencing this.  One dude had a hack to restart poclbm automatically every 5 minutes.  Sounds like a terrible plan to me.

Please help.  Thanks!

[Isepick]

I had this problem in a single card rig powered by an Atom board. I slowed down my overclock on the 5850...problem went away. I think the Atom might have been a bit overtaxed. Every system is different, so YMMV.

[Kluge]

I slowed down my overclock on the 5850...problem went away.

This solved the problem in one of my cards having that issue as well.

[sniper_sniperson]

I got the same problem yesterday so reading posts here minds me that one of the cards has bad bios/bad gpu. This happened on my test cross rig - 5870 + 5850, well after 30 mins the 5870 throttles down and goes to 725Mhz from 870 under linux, nevertheless that the dedicated room has average 18-20'C temp in 48h interval. Under Windows disabling crossfire in the CCC doesn't help, only the second card disappears from GUIMiner's device list. Sapphires are popular with their bad bioses, have 3 5970OC editions and all of them give BSODs unless I change it with ASUS or Gigabyte firms ...

Specs of the rig:
Windows XP 32bit
AsRock N7AD-SLI (sli-singlecard bridge)
E2180 downclocked to 1.6GHz
Gigabyte 5870OC - all leds are in green state
Sapphire 5850 Xtreme
1000W Cooler Master for cards and 400W Fortron Saga for the other components

[picollo7]

Ok, I feel kind of dumb.  With the 4850, I just updated the drivers (including latest SDK) to the latest version, and the problem went away, and I got even better performance.

So, update your drivers if you get this.