Duo Core or Quad Core

I just got a Presario SR5550F with the Athelon 64 Duo core X2. The Mobo specs says it will support a Phenom Quad Core. I am wondering if the quad core will give me a noticable performance increase or should I be happy with what I have now. The specs sheet on this is here: http://h10025.www1.hp.com/ewfrf/wc [...] 40351#N368 I have 3 Gigs of the PC2 6400 if that makes any difference.

I know we have some AMD fanatics out there.... thanks for any input you could throw my way

Quad. Most benchmarks out there will show less FPS on a Duo using todays best GFX cards. For most high end solutions (GTX 260 216 or higher), Duos are CPU limiting the rest of the system.

Unless not building a gaming rig, there is almost no point for a Duo now that Quads are less then $200.