Hi there guys, and gals.

I'm looking to build myself a PC. The things I'm most concerned about right now are the following:

Ram -- Good ram, atleast 512. (256x2)
Processor -- Looking for a P4 2.8
Graphics card -- already have purchased one and have it running in my PC. Works great.
Monitor -- Going to need to get a monitor if I get a PC. Unforunately this will probably cut my budget down.
OS -- Looking to get Windows XP, cheap from somewhere. I currently have it running on this computer, can I install it on a computer I would build? Or would I have to purchase another copy?
Mobo -- Looking to get a good motherboard so I wont have to get a new one for quite some time. AGP 8X, Minimum 2GB Ram. (I'm sure you guys know what's best)

I'm in the budget range of $500-690

I'm going to need a monitor.

Can someone give advice? The parts I'll need for myself to