I made check of my card bios:
https://www.dropbox.com/s/iarrdry9dlhwkz5/2020-04-05 03.03.53.jpg?dl=0

 It reports version F11, when i look at Gigabyte site here:
https://www.gigabyte.com/Graphics-Card/GV-NX66T128D/support#support-dl-bios
   There is bios to download:  X66t7d.f2 

There is also note:
F1, it can only be updated with VBIOS versions F2-F9.
F10, it can only be updated with VBIOS versions F11-F19.
F20, it can only be updated with VBIOS versions F21-F29.

  When i try to flash im getting that my bios is already newer.. So i dunno there is some universal Nvidia bios which is newer and should work.. or i should to force to use older F2 bios and downgrade to it. Im not first owner of this card, so i dunno how bios got there.. I cant find ony other revision of this card.

 

Quote

 Well, if the card would work on Windows ME, then it would mean that there is a problem with Windows 98SE, not the motherboard, or the GPU.

   I can test it easily with WinXP.. WindowsME would be more complicated. Will WinME test tell us something import, what WinXP test wouldnt?

Edited April 7, 20206 yr by ruthan

Windows ME uses the same exact video drivers as Windows 98SE, meaning that if the card would work on Windows ME, but not on 98SE, this would mean that there are no problems with the card, the drivers, or your PC. I've already seen from my experience things that worked on Windows ME, but not on 98SE.
Testing on Windows XP would give us nothing as it uses totally different drivers.

Also, does VBEMP work fine on that card?

Ok.. some news. I tried cleaned drivers which services same behavior.

I tried to disable audio devices in Device manager same problem.

With XP KVM machine its running fine.

VBEMP with 128 card, it completly crashing Qemu when i try to reboot, but i never i tried it with other card.. it could be there with any real physical card.

I will try WinME..

Ok with WinME, same problem.. Bluescreen with Windows protection error, after driver install.

What next, downgrade videocard bios?

I won, its working!

Solution was never Nvidia bios.

Gigabyte flashing utility, really hasnt too much options. So i tried Nvidia NVflash.

 When i tried it, i had problem that some Bioses refused to work because is BoardID - there are 2 variants of Geforce6600GT , ids 4300 and 4301.
I found out that i need bios with ID - p216h1.
When i tried Nvflash, i wasnt able to force bios, but i found that that olded Nvflash (5.93.0.1) has options to overcome it with -4, -5,-6 optimal parameters.

Original bios was 5.43.02.27.00
 when i searched through TechPowerUp bios DB:
https://www.techpowerup.com/vgabios/?manufacturer=MSI&model=6600+GT
  I found that tehre is newer MSI bios (5.43.02.69.00) - https://www.techpowerup.com/vgabios/3163/msi-6600gt-128-050411-2
  I flashed it to card and now its working.

Interesting, it seems that NVIDIA drivers for 98SE do care for GPU Bios...nice to know!

Otherwise VBE are still not working. This corner case, other protection errors have other reasons.. that whay we really need to way how to debug it.. In theory someone really low level should be able to check / trace what is happening with videocard on ASM level.. and make (find) some Dos test utility to check if card is Win98SE compatible.
   I know that same process some used to make WInXP working with newer chipsets.