I am setting up Crossfire for the first time.
I have two HD 4870 cards from Sapphire on the two PCI-E x16 slots on my ASUS Rampage Formula motherboard. I cross-connected them with the two supplied crossfire bridges. I have the option of turning on Crossfire in the Catalyst control center, but I cannot find anything that actually confirms the computer is seeing both cards.

Catalyst control center only lists one 4870 [SyncMaster], and the hardware config in Windows Vista also only lists one. Is this just a single logical card that really represents both cards or is something wrong? Is there any way to actually confirm that Crossfire is working?

Thanks!

Theres no official drivers mayne. I got two of them 4850 n windows doesnt detect both of them unless i uninstall the display driver and install the display driver while both video cards are in system. In crossfire they still suck cause drivers are not mature yo.

I have two 4850's in crossfire. When installing, you should have removed all drivers, put both cards in and connected crossfire cables, then rebooted and installed the drivers while both cards are in and connected. Control center shows both cards UNTIL I activate crossfire. With crossfire activated then only one card is listed. You can run a program like GPU-Z to get more detailed information and make sure both your cards are installed properly, however if both cards weren't I dont beleive the Catalyst Control Center would allow you to check the crossfire box, it would be grayed out I beleive...

Also, make sure after installing the drivers you go to ATI's site and download the Hotfix for the 4800 series. The drivers that are out now are very early stage drivers, ATI should be releasing updated ones soon but until then install the hot fix and it will help with performance somewhat...