my pc restarts everytime I turn it on..but it only restarts while booting so far i haven't experienced any restarting when i'm already on my desktop..and i've scanned my computer a couple of times already no virus.. is it the power supply?

computer:
AMD Sempron(tm) processor
2600+
1.60Ghz, 448mb of RAM

system:
micosoft wondows xp
professional

if it helps..
my AVR brand is DTS Premium Grade MC-500

If it restarts only while booting (?), then how do you get past it?

If it is regular switch on-boot-restart-boot again-normal, I say that it is a BIOS issue. Most probably CMOS battery drained. Side-effects would be loss of system date and time.

2nd guess: BIOS settings are not as they should be. (CPU or memory voltage too low).

3rd guess: one of the sticks/cards is bit loose and doesn't make contact properly.

4th guess would be failed overclocking.

There are more things that could cause restarts at boot-up, but these are top 4.

Thanks! I'll check out all those things you just said to be sure...:)