I have a asus crosshair extreme4 board with updated BIOS and three ATI 5xxx cards, Windows 7. They are not connected with crossfire, and are used for computational research. The very newest ATI drivers are not installed, as the best performance is obtained with these slightly older drivers.
All 3 GPU's work, they have been tested individually.
When I boot after shutting down normally or when I do a normal reboot, only two cards are detected. BUT When I press hibernate, the PC goed to hibernate mode. When I press a key on the keyboard, the computer starts working again, but I don't get any display. I'm not sure if windowsexplorer is actually started during that process or not. The only thing I can do is press the reset - button of my pc, and again it boots. But now all three cards are detected???
How can I make sure they are detected on every boot?