86.5Hz suggests it's switched the resolution to 1024x768 or 1280x1024 interlaced, which LCD monitors generally can't display.
Are you using the Windows or DOS version of this game?
What video card do you have? The Matrox Millennium II?
If Windows 98 thinks your monitor can't handle 1024x768 @ 60 Hz or 1280x1024 @ 60 Hz which would be more appropriate, it can help to change the type of monitor to a different one, even the "wrong" one. Assuming your video card can handle that. Otherwise, you'll need to stop this game from setting such a high resolution--maybe it's hardcoded to look at the list of resolutions and force the biggest one.

The password dialog is to protect people from the blood and gore.
Are you trying to run the 3Dfx version or the software rendered version?
The software rendered version runs at 320X240, but can be made to run at 640x480 with the commandline "carma.exe -hires'. The system in your signature has a VooDoo 1, so I highly recommend you try the 3Dfx version.

jakethompson1 wrote on 2026-08-24, 21:18:

86.5Hz suggests it's switched the resolution to 1024x768 or 1280x1024 interlaced, which LCD monitors generally can't display. Ar […]
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86.5Hz suggests it's switched the resolution to 1024x768 or 1280x1024 interlaced, which LCD monitors generally can't display.
Are you using the Windows or DOS version of this game?
What video card do you have? The Matrox Millennium II?
If Windows 98 thinks your monitor can't handle 1024x768 @ 60 Hz or 1280x1024 @ 60 Hz which would be more appropriate, it can help to change the type of monitor to a different one, even the "wrong" one. Assuming your video card can handle that. Otherwise, you'll need to stop this game from setting such a high resolution--maybe it's hardcoded to look at the list of resolutions and force the biggest one.

Thanks! I set the resolution to 256 colors in Windows settings, and now the game has started 😉

Dorunkāku wrote on 2026-08-25, 00:53:

The password dialog is to protect people from the blood and gore.
Are you trying to run the 3Dfx version or the software rendered version?
The software rendered version runs at 320X240, but can be made to run at 640x480 with the commandline "carma.exe -hires'. The system in your signature has a VooDoo 1, so I highly recommend you try the 3Dfx version.

I lowered the resolution to 256 colors, and the game launches, but it doesn't start in 3dfx mode. I've already applied the patch included on the Carmageddon CD. This is the contents of the folder where the game is installed. When I double-click the 3dfx executable, the game launches in software mode.

So: Carmageddon is installed, official 3dfx patch is applied, I assume Voodoo is correctly set up, i.e. device detected, drivers installed? Your desktop resolution or color shouldn't really matter for 3dfx.

Perhaps give this one a go:
Help getting some 3DFX DOS games to run

Is the Diamond Monster 3D working correctly under Windows and if so, which drivers are you using?

The Windows version is software only. The 3dfx patches available for Carmageddon are DOS only. I'd recommend the Voodoo2 patch even if your card is a Voodoo1, because this version has translucent water effects. Also make sure you have Glide2x.ovl in the same folder as Glide2x.dll or inside the game's folder. There is also a very early 3dfx patch which doesn't rely on Glide2x.ovl but I wouldn't recommend that one because it runs kinda choppy.