6950+6970 Crossfire Issues

[phingocisco]

MSI 6950 2GB / Sapphire 6970 2GB
Asus p8p67-M Pro / H70 Cooler / i5-2500k
Corsair ZX 850w Modular
Kingston 12GB

Okay so this has been bothering me for a few days. Everything in this computer is completely new, in exception of the MSI 6950. Everything works fine in Prime95 and with one video card, either the 6950 or the 6970. When I crossfire the two, thats when the problems start to show. The main card in the slot, either or, gets considerably hot. When I start to play any game though, the computer will completely freeze. At one point I did get both cards running at 54c with 100% fan speed, but then again the computer will completely freeze when playing any game.

I inserted the 6950, uninstalled all the ATI drivers, reinstalled the drivers, inserted the 6970, auto installed the display drivers, turned off the computer and inserted the crossfire bridge, booted up again, enabled crossfire, computer freezes after about 20 seconds into loading Windows.

I did flash the 6950 before, I cant remember when but when i checked both of the cards, the unified shaders are different from the 6970. I did set the Power to 20% on the 6950 on OverDrive... Shouldnt matter though because the 6950 and the 6970 should crossfire regardless. I put both cards on stock settings just to see what would happen, and it was still unstable.

Is it the power supply? The crossfire bridge? Conflicting Drivers? the system is overclocked so i was thinking the cards arent getting enough power. 6950 is 2x6 pins, and the 6970 is 1x6 pin + 1x8 Pin. Any thoughts?

the image is sideways btw... its on a 90 degree case

 

[mosox]

Do you run MSI afterburner?

 

[Emperus]

Your PSU is fine and good enough to handle your system. I guess it is the 6950+6970 combination that is creating the problem. Get both the cards working at the same clocks and try again.

 

[ubercake]

After you added the 6950, did you re-install the drivers?

Everytime I made any sort of physical change to my crossfire configuration, I had to uninstall (using the 'Express Uninstall...' option) the catalyst drivers and re-install them and the re-enable crossfire or else I'd get random issues and crossfire wouldn't enable properly.

I know you said you did the uninstall/reinstall, but that was prior to the change with the 6970 and the auto-install(? windows auto-install should never really happen). So I'm thinking you need to go through the uninstall / reinstall process again.

Your PSU is more than enough even with the OC. Did you test your single 6950 after the flash update?

 

[phingocisco]

Mosox - No

Emperus - Yes iv'e tried that They dont seem to clock at the same speeds though, ill try to get a screen shot up of the differences, 6950's max settings on memory would not reach the 6970's minimal memory. the Gpu clock i had to set @ 800 mhz on both. Did not work as well though.

ubercake - Yeah after i added the 2nd card, i did reinstall the drivers once again. Crossfire did pop up after inserting the card, then turning off and adding the crossfire cable. reinstalled the drivers when that happened. the 6950 flashed worked fine for months, its odd that the unified shaders are not the same as the 6970 though. I will try reflashing it to the 6970 bios and try once more.

If anything i plan on reinstalling windows on a new Hard Drive and do a complete set up once again.

 

[phingocisco]

Okay fresh install of windows + installing Catalyst 11.3 worked. I knew it was the drivers.... 11.6, 11.5 did not work. 11.3 is the way to go it seems.

EDIT: Stable system after 4 days and over applications and gaming.

 

[ubercake]

Yeah. You have to find the right driver release for your cards with crossfire.

Sound like you got it worked out. Hopefully a newer driver release will work better for you in the future, but just in case they don't, keep 11.3 in you bag of tricks.