Hi, I am using dual 4870x2 for windows xp with cf disabled. Now I attach two monitors for two cards and the CAL only recognize two GPUs. Do I have to attach four monitors to use four cards?
Normally you would disable CF to see all GPUs. The X2 cards though, are a bit different and I think, just under Windows, you need to enable CF to see both GPUs (you will need a monitor per card still).
Under Linux, you don't need CF or extra monitors for CAL to see all GPUs.
Give CF a try under Windows and see if that helps.