The Carmageddon 3DFX patches is a bit wrapped into each other. Let me try and explain and see if you guys follow.

Carmageddon initially had no 3DFX support and this was first added with the release of the expansion: Splat Pack (or Carmageddon Max which combined both the original game and the Splat Pack). This version included native support for 3DFX and a patch to add support for the original game (3DFX.EXE). A patch (CARMAV.EXE) was also released online by SCI/Stainless and had several betas from what I can find (first one released beginning of August 1997). The latest official beta version is called "carv24rw.zip" and was released October 25th 1997 with Voodoo Rush support. A couple of months later (February 1998), an unofficial third party patch was released online on Carmageddon.com with the filename "carm3dfx.zip". It is unknown what this adds, but it is speculated that this patch works for more versions, even the censored German/Australian versions.

In July 1998 the alpha Voodoo2 patch was released. It had no technical support and it was created by a member of the Stainless Software programming team in his own time for no reward. The Voodoo2 patch includes executables for both the original game and the Splat Pack. It requires the final beta patch (carv24rw.zip) to be installed. The game can be run with VOODO2C.EXE for Carmageddon and VOODO2S.EXE for Splat Pack. It supports all versions and removes CD check. I dont see why the Voodoo 2 patch shouldn't work with Voodoo 1 cards tbh, but I have not tested this personally.

There is also an unofficial installer for the 3DFX patch, but I haven't tried it. It reads:

This is an unofficial hack to help people which were having problems installing the 3DFX patch.

Jeeze.... What a mess! I'll try these out and see how far I get. Thanks!

Making SOME progress - got Fatal Racing and Shadow Warrior working with my 3DFX Monster 3D card. Screamer 2 is proving to be a real bitch ( for lack of a better word), as is Carmageddon. With Screamer 2, I'm getting a "GrSstOpen Failed" error, after trying %PATH% route. I don't seem to have a "HOTCGL" subdir in my game directory, but even when coping the Glide2x.ovl and Glide2x.dll in there, still no luck. I believe GrSStOpen was only used with Glide 2.11, so I grabbed the Glide.dll from the SDK and tried using that, but no luck there either. I wasn't able to find a Glide.ovl file for it like I've seen with the Glide2x.dll's. PErhaps someone can clarify what these files do?

I tried the GOG version of Carmageddon with the 3dfx patch, but I'm only getting a black screen. Ready to throw in the towel on these very soon. GRRRR.

I have to admit that I like a voodoo1 more than the voodoo2...it was a game-changer when I installed it in my P166 (later a 200mmx).
I currently have a project Scenic Pro-C6 (D1026) (Celeron 300A, 192MB Ram, 40GB HDD, Voodoo1 and Matrox Productive MGA100A Onboard (2MB+2MB(Upgrade), Dos622+Win98se)
I checked different drivers and the best one I could get was the "2.46 reference-driver". I found no (win)games that do not work or produce graphical errors with this driver.
For Dosglide you have to use older drivers. (glide.ovl).
Generally I prefer gaming in 512x384 mode because it's MUCH! faster on voodoo1 and there a no significant image-quality reducing.
Some games do not offer a 512x384 mode and perhaps they can be tweaked. Hopefull I can get some Infos how-to.