computer loops on and off

here is my problem, my computer starts and then before it displays my desktop and restarts again and again even in safe mode running xp and do not have a floopy disk and it is an ABS computer
thank you

 

bud, something you should always do with your computer, is in System, Advanced System Settings, Startup and Recovery. Always ensure that Automatically Restart is NOT ticked! Otherwise this will happen, if you have your original CD/DVD run it and get to command prompt (simply click command prompt, press r when asked for XP), then type;

FIXMBR

you will be asked .. are you sure you want to do this?? press y, then type

chkdsk /r

once that is complete, try to boot again, without the CD/DVD in the drive, if it works, once booted, put the CD/DVD back in the drive, reopen CMD and type;

sfc /SCANNOW

once that completes, simply make sure you untick that box!! If it didn't boot however, open your case, clean the inside of it, remove your RAM sticks, get a CLEAN rubber and CAREFULLY rub them up and down the gold contacts, being careful not to touch them, you should hold your RAM by its ends, once you've rubbed the contacts, brush the stick over lightly, brush the seat, and re-insert the RAM, ensuring it round the right way ... the RAM is the most common culprit of blue screens ...