DOesnt read my OpenGl

Dell XPS__T
700 MHZ
NVidia GeForce256 4x APG

okay, my OpenGl was working fine until about 2 weeks ago, i installed the Detonator2 again because it got screwed up the first time and now all of a sudden my OpenGl is non-existent, i cant play anything, my Direct3d still works but none of my games notice the OpenGl and i have reinstalled the drivers, including Detonator3 many times trying to maybe find the problem, but it still exists, can anyone give me a few tips on what to do because Nvidia and Dell have no damm clue…thanks