r112029 wrote on 2021-01-09, 17:18:

Hi! New user here, been lurking for solutions etc for years but I'm completely stuck on this issue and haven't found anything on […]
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Hi!
New user here, been lurking for solutions etc for years but I'm completely stuck on this issue and haven't found anything on Vogons or anywhere else to solve it.
I have an old Deskpro system (I think its an EP 6450 but not sure, the CPU might have been changed, but its originally a P3 system anyhow). It has the I440 chipset and 686T2 ROM family . It has a factory mounted Matrox G200 AGP card and it works fine, but if I try switching out the G200 for another AGP card the computer won't boot, it just gives me the error beep code for GPU error. I've tried a Riva TNT and an ATI Rage 128 pro, both with the same results. It will boot fine with any older PCI video card though, I've tested a few, it even boot fine with any PCI video card + the TNT/Rage card in the AGP slot and in Windows it even detects the TNT or Rage card as a display adapter, but it just wont boot with only the TNT/Rage card in the AGP slot. I've tried flashing the BIOS to the newest I could find, it gave me some new AGP-related options in the BIOS setup (specifically adjustable AGP aperture size) but it didn't solve the problem. Any help here would be very appreciated, the G200 is cool and all but the driver support for DX/OpenGL games sucks so I'd really like to get a nVidia AGP card in there 😀
Thanks in advance!

Have you managed to solve this issue by now?

Kinda odd that this thread went unnoticed btw, but it's much more difficult if we don't know the part numbers involved (or pics of the Compaq as it may be proprietary in some way which is causing these issues). Could even be the PSU but somehow I have my doubts about that one for now.