Setting up CrossFire

[TotalLamer]

So my new case (CM Storm Sniper) along with a pair of 5870 Vapor-X cards came in the mail yesterday, so I set about swapping everything from my Antec into the CM, as well as installing the new cards and replacing Win7 RC with Win7 Sig Edition. In any case, everything went fairly well (although now that I have the case on the desk instead of below it, I've suddenly noticed just how LOUD my VelociRaptors are) but the machine is a bit iffy about recognizing both cards. The first few times I booted it, all that showed up was the primary card. Once it did recognize the secondary card, and activated CrossFire, but after another reboot... back to just one card.

Is there a specific procedure needed to get CrossFire working? That is, should I have installed the drivers/CCC with just 1 card installed, then shut down and installed the 2nd, or.... ?

 

[Checkemdown]

Download GPU-Z and it should tell you whether Crossfire is enabled or not. It should also tell you whether both cards are detected:

http://www.techpowerup.com/gpuz/

If Crossfire is disabled, then you might want to check your BIOS settings to make sure all of your PCIe slots are activated. Some BIOS's disable the second lane for some reason and it has to be turned on manually. Not sure how it is with MSI, but since it has already recognized the 2nd card at some point that might not be the problem.

Also make sure the Crossfire bridge is connected properly and try it with 2 bridges and see if it makes a difference.