For my compaq computer, on board video card can not be disabled using the motherboard. It must be done using the BIOS. It is kind of funny that it does everything automatically..... it automatically disable itself when a new PCI video card is installed(not all the time). I was able to get many valuable information from compaq forum. I think ACER may have that too. Check ACER homepage and see if there is any site like that.
PC133 128MB ECC
WD SCSI2 10K 5.2ms 18.3G
Vortex2 w/ digital out
Sony MHC-5500 Digital Signal Processer - 30 equalizers and Dynamic Sound