I have a computer with a BIOSTAR 865GV Micro 478 Motherboard. It has a Intel Graphic Card onboard, to get a Dual Head Display I but in a Matrox G450 Dual Head DVI Graphic Card.
Now every time I try to disable the Intel Onboard Graphic Card in Windows, the screen just stays black, although the Graphic Card shows up as installed, it's not used by Windows. Disabeling the onboard Card in the BIOS is not possible.
I tried to disable the Graphic Card in Hardware Manager, I tried to uninstall the Driver for the Graphic Card.
The Graphic Card is only used when I boot in Safe Mode or in VGA Mode.