8rda3+ Re-booting

System specs:
8RDA3+
AMD 1700 DLT3C
2x256 Buffalo pc3200 running in slots 1 and 3
40g Maxtor
Windows XP sp1
running 8.5 x 200
SLK-800A/Smartfan II

This is my oldest daughters rig, and is not heavily overclocked. CPU temp has never been above 50ºC

Problem:
Machine has been running fine for several months. The other day, she went to shut it down, and it re-booted. Upon re-booting it went into scan disk. I ran AVG and Panda scan, no problems found. Machine runs fine otherwise, but re-boots on shutdown. Although last night she told me it re-booted all by itself (it was running idle at the time) and went into scan disk again.

A person I trust very much said it sounds like the memory is being dumped on shutdown. This makes sense because the scan disk always finds the same file with incorrect size: ntuser.log.dat (or maybe it's ntuser.dat.log I can't remember which) which seems to indicate that logout is not being accomplished correctly.

So,
Does this sound like a hard drive failing? Or a bad memory stick? After Christmas morning I will have some more RAM to swap into it (the new RAM is waiting under the Christmas tree for one of my younger daughters to discover she is getting a new rig). I will not have a spare hard drive to test since I am re-using the hard drive from my other daughters machine in her new one.

Any help would be appreciated.

Thanks

UPDATE:

I went ahead and opened the new Buffalo ram and stuck it in. Same results. Tried each new stick in slot one also, no help.

The file found in scan disk is ntuser.dat.log

Probably a capacitor problem. Open up the case and check the capacitors for bulging and leaking.

Already checked the caps and fets. Bad caps would have other symptoms besides a mem dump on shutdown.

Try running System File Checker in System Information for missing or corrupted System Files.

Regards, Balrog

Cuda said:

Already checked the caps and fets. Bad caps would have other symptoms besides a mem dump on shutdown.

Click to expand...

But, you also said that it was rebooting on it's own even when idle.

Yeah, it did it once. Anyway, here is an update:

I went to run system file checker, only to find that the files could not be found. I re installed Windows, and had another re-boot. This time, however, the error report to Microsoft yielded a response. It claimed that InCD 4 was causing the problem (makes sense, I forgot that I had installed it a day before the problems started...duh). O.K. Uninstalled InCD 4, re boot problem is gone. System shuts down normally. BUT now the CD RW drive is no longer recognized. I un-installed it in Device Manager and when I went to re-install it with the add Hardware Wizard, it finds it but cannot complete the installation. The driver files appear to be corrupted or missing. Since the CD rom wont turn up, I can't load the drivers from the Windows disk. I couldn't find any drivers on Lite Ons site for the drive either. I have that machine on the network, so I am going to try to load the drivers from the XP disk while it is on this (my) machine. What I find odd is that the CD RW wont spin up. When I put a disk in it, the activity light on it flashes, but it doesn't spin up.