Hi, and welcome to the Geeks to Go forums
(That said, I'm brand new myself!
)
Looking at your post on the MaximumPC forums, you seem to be very serious about gaming performance. If you intend on building a PC capable of handling the latest games at good resolutions and smooth frame rates, expect to shell out $1000
at the very minimum. At the time I built my system, it cost me around $1200 and it runs FarCry smoothly at 1280x1024 resolution and maximum graphic settings. I consider my system specs adequate for my personal gaming needs. You probably won't have to pay as much as I did, since you plan on reusing some parts. However, I'd still suggest you get another 512 MB of RAM to bring your total RAM up to 1 GB. (Make sure the speed of the RAM you buy is equal to that of what you currently have.) Also, I think an Athlon 3500+ is a little overkill for you -- anything above an Athlon 2600+ will suit your needs just fine. Get a video card with 256 MB of memory, and you should be pretty much all set for rock-solid gaming stability (as far as the hardware quality goes) and relatively high-end performance.
Your CPU link is pointing to a motherboard, and your video card link to a CPU, so I can't tell what video card you have in mind. Hope this helps.