For some reason, my computer has gone crazy and just stopped working. Finally my brother came in and said it was probably my RAM cuz its an older computer, so we tried some different ram and it still didnt work. We figured maybe power supply? We tried that and that didnt work. So we tried both, and it came back up. He put in his Ultra 500w X-connect PSU and a stick of OCZ 3700 EB Platinum RAM which was 256. It worked. Well for Christmas they went out and bought me a stick of Kingston 512MB pc3200 RAM and an Antec 350w PSU. What sucks is that the psu has a 24 pin connector, but the x-connect psu had a 24 pin too and it still worked fine. Well now that we've put those parts in there, its still restarting. What could it be? It gets to loading the windows xp screen, then right after it restarts....? Please help

Also, the computer consists of a KR7A-RAID motherboard, 512mb kingston pc3200, antec 350w atx 2.9 psu, just put a BFG 6200 OC AGP card in it, cd rom, cd burner, floppy, soundblaster card, network card, athlon 1900+ with a big volcano 7 fan.

So the problem started AFTER the graphics card was added? Is the PSU up to it?

Try this. XP may have decided you have changed too many components and thinks it is a different machine.
How to do a system repair.--Boot from the xp cd and go past the recovery console to the install menu. Select repair the existing installation. You won't lose any data except the xp updates. Unless you have a slipstream sp1 Or SP2 cd you will have to d/l sp1 or sp2 and all subsequent updates. You MUST have at least SP1 installed and the updates for security reasons. Be sure the firewall and A/V is active before going online as you will be susceptible to sasser and msblaster.

http://computervitals.com/