TNT 2 ultra versus GEforce in open gl??

I have just played this brilliant game MDK 2
Its really use open gl to its limit.
Most spectacular game Ive seen.

My Question is if I have a Geforce instead of my TNT 2 Ultra are there effects only seen with Geforce cards??


but you cold crank up detail levels all the way

I can run the games with highest graphic settings today but its probabaly because my monitor is limited to 1024*768.
If i buy new monitor I believe I have to buy a geforce as well to play at high resolutions.