My PC has been powering down and rebooting after exactly one hour every time I turn the thing on. It's been happening for about 3 weeks now. The spec of my self-built machine (rough in places sorry) is below:
- Built 2007;
- Windows XP SP2
- Intel Core 2 Duo 2.2Ghz E4500 with standard fan and heat sink;
- Intel Motherboard (cant remember if its the DP3DP model, but this was what I wanted originally, so if not that then very very similar);
- 2Ghz stick of DDR2 RAM (fitted approx 2008-9);
- ATI Radeon X550 256Mb Graphics;
- Xilence Power PSU XP600.(12)R 600W ATX 2.2;
- Seagate Barracuda 250Gb HDD;
- Generic CD-RW;
- Pro Tools MBox2 Pro via Firewire;
- Logitech Driving Force GT Steering Wheel;
The specs are outdated but it was built as a specific music PC and for playing literally one offline game (and still is).
This PC has never had another user other than me (literally no-one else has touched this PC), and has never been connected to the internet in any way. I do not use the Task Scheduler, and nothing is being written to the Event Log, nor is there a BSOD. I have un-ticked the 'please don't auto restart this machine' box yet it still doesn't show me a BSOD. It will just shut down and restart every hour exactly ad infinitum. This PC isn't even used every day, possibly twice a week depending on projects or free time to play GPL lol.
I have not installed anything on this PC for about a year, it receives regular de-frags and file checks, and only official released software has gone onto this machine so I can rule out viruses.
I have ran the PC idle (case on and off), in Safe Mode, in CMOS (BIOS...whatever), and it will still reboot. I ran Memtest in it's standard tests (not the longer test) and it brought no errors. The temps for the CPU look ok, and the Voltages for the PSU look fine with no drops.
So, I have ruled out the OS and software, Scheduled Tasks, the RAM, the Graphics Card, overheating and the HDD. There are no bulging or broken caps on the motherboard. I would also rule out the PSU given it is still running fine and there are no voltage issues, but that is the only thing left.
I was ready to buy a new PSU, but a tech friend suggested he had a similar issue caused by the RAM which doesn't make sense to me. Yet another tech friend has suggested that it is definitely the PSU as he also had a similar problem, and the internet (and therefore the whole world's population) is undecided.
I don't want to stump up the money for a PSU that I don't need (and can't really afford), so I need to be 95% sure. I'm 90% sure atm, so your advice would be really helpful.
Thanks in advance Tom