Please help, OpenGl/Tnt2/Halflife problem

I have a TNT2 M64. 90% of the time i try to join any multiplayer game of halflife, team fortress, counterstrike etc. with OPENGL on, I get a fatal exception error(aka BSOD), It closes halflife, shoots me back to windows, and i have to reboot because when i try to start halflife it says i dont have DirectX 6.0 or higher Installed.
I have DirectX 7.0 installed actually.
I have tried it with 2 differant TNT2M64’s so i know its not the card (although it may be the chipset). Ive reinstalled halflife, directX, windows, and it still happens.
Any ideas?

[This message has been edited by S4S (edited 11-25-2000).]