Hi computer experts

Couple of days ago I upgraded my 16 RAM to 32RAM and my creative 3D Blaster Voodoo2 8 MB was working fine untill yesterday. Whenever I play games which use my 3D card (they were working fine before) THEY LOOK REALLY DARK.
I went to display properties and changed the gamma correction still doesn't work. I have installed the latest drives with DirextX6 still doesn't work.
Please can anyone help me out