How to get Crossfire working

[eimz]

I recently upgraded to Windows 7, 64bit ultimate. I have two (x2) Radeon HD4850 Graphics cards. In the past (with win XP) I didn't have any problems getting them both to run in Crossfire; however, ever since going to Win 7 I can't get Crossfire to work. In GPU-Z both graphics cards are detected, which is also shown in Windows System Information.

I have the latest version of Catalyst Control Centre (CCC) installed, which shows both graphics cards; however there is no Crossfire option in the Performance Section. When I select Hardware it shows that the second graphics card as a Disabled Adapter. Am I missing something really simple?? Both graphics cards are powered and they are both connect using
two crossfire ribbon connectors.

Any help appreciated.

 

[jeepster50]

Make sure drivers are installed for both cards.

 

[eimz]

Both cards are Gigabyte HD4850, and I have already installed the latest drivers from the ATI website (Version .872.0.0 dated 7 /07/2011). I have checked and the Windows device manager shows that both cards have the latest drivers.

FYI, with my old system (MSI X48C mainboard (piece of crap!!), Q9550 processor XP 32bit OS) I had no problems getting Crossfire to work. Unfortunately, the system was incredibly unstable due to the motherboard, causing me to recently upgrade to a P8P67 mobo, i5 CPU and OS switched to Win7 64bit.

Both cards are powered, and are connected using the two Crossfire ribbons. When I open Catalyst Control Centre the Crossfire option is not even there. I thought it should automatically appear??

BTW CCC shows one card as the Primary adapter and the second as disabled. Is this right??

 

[eimz]

Figured it out, due to Crossfire limitation, the PCIe x16_2 slot had to be changed in the bios to x4 mode to setup a Crossfire configuration.!!

 

[medjai07]

there is no tab about pci limitation
about pci i have thesee pci---peg--peg1--peg2---peg3--peg4