Hey all, I've recently gotten Apple's HD5770 Graphics Upgrade Kit for my Mac Pro (2008 / 3,1) - I previously used a 8800GT which died. As I also use it for some gaming, I have a HD5970 in there to run DX11 games smoothly on my 30" Cinema Display. However, since I installed the graphics update from software update to give drivers to my HD5770, the machine kernel panics when starting up with the HD5970 installed. This wasn't an issue previously: the two cards coexisted peacefully (the geforce and the HD5770 without drivers). My guess is that OS X tries to load drivers for the HD5970 and kernel panics on this phase. The HD5970 is installed in slot 1, the HD5770 is installed in slot 2. Are there known issues like this? Any workarounds? Could I perhaps edit the device ID of the HD5970 into a kext to get it ignored by the system? Does the slot layout matter at all? Thanks so much guys.