What would be a great video card for games such as Mass Effect 2, Napoleon Total War, CIV IV, and Borderlands?

I got Nvidia Galaxy 8400 GS about 2 months ago, and it' not catching up with the latest games. I am going to get a bunch of games soon (some listed above) and I need them to look pretty disent. Games such as Mass Effect 2 and Napoleon Total War, I have to play on minimal reslolution and graphics settings on low for good performance. I'm thinking of getting a more powerful video card but not too expensive. Any edvice? Thanks))What would be a great video card for games such as Mass Effect 2, Napoleon Total War, CIV IV, and Borderlands?
The 8400 is not a gaming graphics card. That series of graphics card judges power by the hundreds place (200,400,600,800). 8800 GTX is a great graphics card and not too expensive. The only thing is, you may need a larger power supply unit. The 8800 will run a lot of games smoothly for a couple more years.