NT4 SP5 with dx5 patch. Works
with glide. 
To get it to work: 
1. Hit okay on the directx errors during install. 
2. Change byte 1D55C6h of gta2.exe from 73h to EBh with a hex editor. (this
disables the directx version check) 
3. Open regedt32.exe and change: HKLMSOFTWAREDMA Design LtdGTA2Screenrendername
to 3dfx.dll and HKLMSOFTWAREDMA Design LtdGTA2Screenvideoname to
dmaglide.dll 
4. Run gta2.exe. 
The options menu doesn't work

During install it says that
you need DirectX, just hit OK. IT will give you some errors during
install but it works fine!

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