How do I know what kind of video cards my computer will support?

Currently I have a GeForce FX 5200 with 128 MB memory, 8X AGP, with S-Video and DVI out that came with my system. Will I be able to upgrade to another GeForce video card without any problems?|||As long as it's AGP.|||You can get another video card, as long as it's AGP. The fastest AGP card on the market Right now is the ATI Radeon 1950 . It's just a hair faster than the Nvidia 7900 GS. Which is also available in AGP. Expect to spend about $150. Either one is much, much faster than the FX 5200.