Well, there are no official (full) Drivers for WinXP.
That's the reason the original (Win2000) Drivers never worked well (if at all), and the default Driver coming with the WinXP installation is a mediocre DirectX only Driver (no OpenGL/Glide).
So the Problem likely isn't your Game nor the Voodoo3. It's WinXP actually.
A Tech handed money will likely only try to sell a new Card I'm afraid.
My advice :
http://www.falconfly.de/voodoo3.htmScroll way down to the Voodoo3 WinXP Drivers (3rd party)...
You'll see that the Amigasport 3.0 is the latest one, but there are a number of older releases as well.
Installing the old ones is a bit more painful, but the few steps needed are simple.
If the 3dfx Tools says it had an error after installing the Driver, just click okay, but do
not reboot when prompted.
Install the 3dfx Tools again (setup is found in the Driver Directory), and now you can choose "Repair" as an Installation Option.
In most cases I know of, that solved the Problem, and now after a reboot, you got the Driver + 3dfx Tools correctly installed.
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Basically, I would work my way up, starting with the
oldest Voodoo3 WinXP Driver first.
If the game still fails to initialize Glide, walk your way up in Release dates....
A bit of work, but I'm afraid it's the only way (under WinXP).
Running a 3dfx Card under WinXP is simply not the best Operating System; all Glide Games were originally developed for Win95/98.
Last hint : If the Game refuses to initialize alltogether, using the WinXP Application compatibility Option might help (sort of fools the Application to think it's running under an older OS like Win9x )
Bottom line is :
You'd be way better off with Win2000 or 98SE on your machine (with it's current Hardware)