This is useful for Voodo04 and Voodoo5 cards with DVI output. Setting some resolutions, like 1920x1080 (with default timings), would result in VGA outputting a correct signal but DVI outputting 960x1080. The issue is triggered by the total horizontal width (active area, porches, sync). One way to get around this was by using Dolenc's timings provided here The Changeling 3dfx Voodoo 5 5500 . This fixed the issue with digital video output, but, at least for me, broke VGA. I could never have both working at the same time.

Attached vsa100_modefix.exe. Just run it against the .sys or .vxd, eg:

Windows 95/98/Me MiniVDD: vsa100_modefix.exe 3DFXVS.VXD
Windows NT 4 miniport: vsa100_modefix.exe 3DFXVSNM.SYS
Windows 2000/XP miniport: vsa100_modefix.exe 3DFXVSM.SYS
Community 64-bit miniport: vsa100_modefix.exe 3DFXVSM64.SYS

It will patch it after creating a backup of the original driver. If the release isn't recognized, you can also try with --force : vsa100_modefix.exe --force 3dfxvsm.sys

After patching, install the driver normally. Regular timings can be used and both DVI and VGA should work properly.