Continual lockups

Hello all - first time poster <waves>. I just finished building my second PC (so I'm a newbie at this) and I'm having lockup problems that seem to be hardware related and was hoping someone might have a suggestion as to how to narrow the list of suspects down.

My build consists of:

Asus P5N-E SLI 775 Motherboard
Intel Core2 Duo E6850 3 Ghz Processor
PNY GeForce 8800 640 MB Video Card
Corsair 2048 MB Ram (x2)

I assembled all the parts, installed the SATA hard drive I had from before (deleting all old drivers and replacing them with new), but the computer kept locking up. Sometimes it was during Windows loading, sometimes just while it was sitting there in Windows and other times after a game or IE had been loaded and was running. After trying everything I could think of, I decided to reformat the hard drive and reinstall everything, thinking I might have missed a driver or something that was causing a conflict. Now, everytime I try to install Windows XP, it locks up on me during the install (at different points each time, anywhere from 2 minutes up to 18 minutes into it). Since I have no real software now, I'm guessing it must be one of the hardware components. Any ideas on what it could be and how I could check?

Thank you for your time

 

check the voltage on the ram and see if its 1.8 1.9 etc and make sure bios is giving it enough juice also post power supply specs (12v rail amperage, wattage, etc)that rig will be power hungry

 

The voltages listed by BIOS are:

Vcore Voltage: 1.29V
3.3V Voltage: 3.32V
5V Voltage: 5.02V
12V Voltage: 12.03V

The power supply unit is 700W.

If that was not all the information you needed, please let me know (along with how to determine it). I am trying to learn all this and greatly appreciate any help.