Well i have a Biostar 7600GS, down version of the GT, and its great card for the price. I play CS 1.6, and get constant 100 FPS in about 5/6 smokes, but I play @ 800x600 resolution, but it still plays higher ones w/ 100fps in about 2 smokes, then it starts dropping, remember thats with my GS, your GT will be better. You'll see an amazing increase with that card from your 6100 onboard, I know i did.