This is an HP Pavilion 533w running Windows XP. According to the owner, it's been working fine since 2002 (yeah, it's pretty old, but I'd like to fix it if I can). Then, just recently, it started shutting off a few minutes after being turned on. I opened it up and noticed that when it shuts off, only some components stop working. For example, the power supply fan continues to spin, but the case fan and the processor heatsink fan stops. The power LED on the front turns off, but the hard drive indicator lights up continuously. In addition, the hard drive continues spinning. If I hold the power button down, everything will power off completely.
I suspected it might be overheating, so I let it idle for a while at the BIOS screen, but the temperature stayed steady at 38°C. Then I popped in the Ultimate Boot CD and ran some stress tests, but it worked fine. Then, I thought it might be a problem with the power supply itself; maybe it would stop supplying power to some of the cables, so I tried a power supply that I know works, but that didn't help.
When Windows boots, it wants to run
chkdsk, which I allow it to do. It finds a few problems, corrects them, and then the system powers off at around the end of step 2 or the middle of step 3. If I skip
chkdsk, I can get to the desktop, but then the system shuts off between 3 and 5 minutes later. This made me think it might be a problem with the hard disk, so I ran MHDD32, but it reported no problems. I then booted a Windows XP Recovery CD and ran
chkdsk from it, but it finished without problems.
At this point, I'm back to thinking it's a heat issue, but I'm not sure where to go from here. Does anyone have any suggestions?