Strangely annoying bug thingie?!?

Whenever i play games (Quake, Quake II, Half-Life) or build models (in MilkShape3D) The models and onscreen weapons have a red, blue or green transparent texture like thing over their normal textures. The normal textures are shown only when the model’s triangles are touching the edge of the screen.
I have tried downloading new drivers for my TNT but all the files on are corrupt. My drivers aren’t older than 1 month. I’m also pretty sure that the new patches for the games wont help this because it happens in more than one game. Although most are the newest versions.
When I run a game in software mode, the textures are normal but slow because the lack of graphics acceleration.
I think that the fact that all these programs that I have named use the Quake Engine may play a part in the problem, I have emailed Valve and Sierra, no replies yet.
Any suggestions at all will be helpful.

Ergh, do u have a TNT or TNT 2?
And what’s the version of detonators u r currently using ?

TNT1, with (it was the only one i found that STATED that it was for TNT1 aswell as the other chips).

Hmm, did u try using older drivers? I am not exactly sure if 10.80 is good for a tnt1. Try the original 6.50. But make sure u uninstall current drivers first