Upgrading my computers video card?

I have a AMD Athlon 64 X2 Dual-core Processor 3800+, 250 GB 7200 RPM Hard Drive, 2048 MB DDR Dual-channel memory, NVIDIA GeForce 6100 video card.

I am not super good with computers and don't have much experience installing new components into the computers and so I wanted to know if any NVIDIA GeForce 7800 video cards (Under $400) will be compatible with my computer, and if so what else do i need to run it, such as power supply that meets the cards needs, or any cooling devices, or more memory or anything like that.

Thanks

Upgrading my computers video card?norton 2008

It really depends how much you are wanting to spend and what sort of PSU you have.

For under 200, you're probably better off with the radeon x1600 series or the geforce 7600 series.

For 250 to 300 I'd go with the 7800 GT or 7900 (7900 GT runs more or less equivalent to 7800 GTX) or the x1800.

If you want to buy the farm, go for the x1900 xt or the 7950 GX2/7900GTX.

Beware that a lot of these take up a good amount of power (seen below):

http://images.anandtech.com/graphs/7900%...

Your processor will take up about 170W at load itself. So you're probably looking at wanting at minimum a 400W power supply for the midrange of these cards and maybe more for the big guns or SLI/Crossfire caliber solutions.

As for the choice between ATI and Nvidia, well right now the prices are very similar and the performance is also quite similar. I don't want to say one is better than the other, because really they are not. Right now though the ATI cards tend to take a little more power on average and run at higher temperatures.