Value (Price/Quality) for Computer Upgrades?

Sierpinski asks: "I am currently researching a new video card, and seeing that PCI-Express has pretty much taken the industry by storm, I have not been able to find a relatively recent (late-model so to speak) AGP card. If I get a PCI-Express card, I'll need to upgrade my board. If I upgrade my board, I doubt my CPU (slot 462) will still be usable. As much as price is a factor, compatibility is as well. I've run into problems in the past where X memory wouldn't work in Y boards, etc. Does anyone have a spec list of the main components (board, CPU, memory, video card) that are recent (ie 6800GT PCI-Express), and work well together?"