Video Card for Games (Precision 490) - Suggestions Please

I got a great deal from the Outlet store on a dual processor Precision 490 (2 Xeon 5150's, 2 gigs of 667 RAM, Quadro 550). I'm into gaming, but because I will be doing a fair amount of home video editing (Premiere Elements) & DVD burning, as well as some digital photo work (Photoshop Elements), I went with the 490 instead of the XPS 700. I also got a 2407 WFP monitor. I don't max out my gaming settings, as the "average" video settings in the game options look fine to me. I admit I'm second-guessing myself on whether I should have gone with the XPS 700, but that's a done deal, water under the bridge, etc.

 

My problem is that I think this rig would be great for gaming, except for the video card. Any suggestions on a gaming card that would be compatible with this system? BTW, I usually go for the "sweet-spot" on the gaming card performace curve, which means I don't go for the bleeding-edge top-of-the-line cards. On of the things I'm considering is keeping the Quadro 550 until some reasonably-priced DirectX 10 cards hit the market.

 

Any suggestions would be greatly appreciated, as well as thoughts on to how well this setup will perform in the video editing & gaming area.

 

Thanks,

 

Bert