auto-restart & config problem

[dhellhk]

okay, a month ago, i reformatted my computer (2 month old) because it kept getting the blue screen of death, as microsoft calls it. Right after windows fully launched, it auto-restarted (no warnings) after it restarts, it works thoough but after a while, it restarts by it self again at a random time (no warnings). Today, i got really annoyed by it, so i decided to reinstall windows XP. now, when i boot it says:

"Windows could not start because the following file is missing or corrupt:
\Windows\system32\config\system

You can attempt to repair this file by starting windows setup using the original setup CD-ROM.

Select 'r' at the first screen to start repair."

When i do that, it loads normally until the thrid screen, then it automatically restarts and if i try that again, it automaticalyl restarts and goes in a repeated cycle. If i do not press 'r' during the first screen the error message occurs!!! Some1 help?!?!?

Thanks in Advance

Richy

[edit]
even loading in safe mode the error occurs!!