Computer keeps restarting on pressing the start button

qadirv

Honorable
Sep 29, 2012
1
0
10,510
Hello,
I'm fixing a computer for this kid, and the computer keeps restarting. (or so that's what i believe. The screen flashes "cable signal missing for a milisecond". :D) . The screen flashes about 3 or 4 times and then computer shuts down automatically. This whole sequnce of events happens within a period of 15 seconds.
After Cleaning out the heat sink, and basically the whole motherboard of dust, the kid tells me that he deleted the whole C drive.
I tried using a XP CD, as well as a bootable pen drive. Nothing works.
I also tried disconnecting the hard disks and trying, removing the round battery and replacing it, but am not able to get anything up on the screen.
My only thought is that that the power supply is gone.
i'm not sure what else to try. This kid cant afford to buy a power supply to test, so unless i'm 100% sure it's the power supply, then only wpould i tell him to go get one.

Are there any more things that I could try to get this computer to work??