If you need all those parts for under $500, figure it out in reverse. How much RAM do you need? It will probably be DDR RAM, and 512MB seems popular so... ~$150 for 512MB DDR, leaving you with $350. You can guestimate an average of $100 for a reasonable motherboard. Not too many frills, but not a stripped bargain basement board either, leaving you with $250. If you're not going to be overclocking (which you don't mention) then you can use either retail box HSF or a cheap aftermarket unit. Let's start with retail box (since it IS adequate for non-overclocked systems). Hmmm, under $250... leaves you with a LOT of choices. You can get P4 2.4B for around $200. Athlon 2400+ is similarly priced. This leaves you with $50 to pay for tax and shipping, LOL. As to AMD or Intel... your call. The AMD actually runs at 2GHz, but still gives great performance. With Intel you get a very cool running processor with a relatively quiet HSF. Flip a coin.