My daughter’s computer (a Gateway, Windows XP machine with an AMD CPU - sorry I don’t have other details available right now) has a nasty habit of rebooting itself at random intervals. This does not seem to have any relationship to what programs are running. It can just be sitting there at the Windows desktop doing nothing, or it can be in the middle of doing something; suddenly it will shut down and restart itself, and soon will be back at the Windows desktop with any programs you might have been running closed down and any unsaved data lost.
I am fairly sure that this is some sort of hardware issue, but I am not very knowledgeable about hardware, and I cannot figure out what. There was some malware on it a while ago, but I restored the operating system (it has a system restore partition on the hard drive) wiping all user installed software, which seemed to cure the malware, but did not fix the rebooting problem. Indeed, it only seemed to get worse (more frequent) with time. My initial, uneducated guess was that the problem might be due to a faulty power supply, but that has been replaced and it does not seem to have helped.
A few months ago, my wife got a friend of hers, Gary, who, apparently knows a lot about computers (I am not sure if he is an actual professional), to take it away and work on it. According to her (I am relying on her second-hand reports here), he had the thing disassembled, and ran lengthy tests on the motherboard, power supply, and other components and could find nothing wrong.
(It occurs to me, however, that if she did not clearly communicate the nature of the problem to him, he might simply have been leaving it running Windows overnight. As it reboots quite nicely to the Windows desktop, it might appear to be fine the next morning even though it might have rebooted several time when no-one was looking. I have not met Gary, and my wife’s account of what passed between them has not been all that clear.)
Gary then reassembled it and (pointlessly, in my view, since I had already restored the OS without avail) wiped the hard drive, and replaced the original operating system (which was XP Media Center) with his own copy of XP Professional. At this point, apparently, the guy fell ill, and we did not get the computer back until several months later. It still randomly reboots.
Can anyone suggest what the problem might be? It has occurred to me that (if the story is being conveyed to me right) if Gary was truly unable to reproduce the problem while he had the machine, maybe the problem might have something to do with the power supply at the house. Although several other computers have been and are currently in use there with out any similar difficulties, could this Gateway be particularly susceptible to mains spikes, or something? Could that cause this sort of problem?
Or…what else might it be?