Computer reboots while idle?

[Elku]

This is has been happening before, but it somehow fixed itself after a while, and now it's starting again!

-How the bug is triggered:
I go to sleep and leave my computer open for the night... when I wake up I notice the computer has rebooted. Been doing that for like 3 nights now. I've been on the computer for the whole day today (so 8 hours+) and it hasn't rebooted once. I have screen saver turned off and all power management thingy to off.

-What I have done so far:
Spybot S&D scan, was clean. Hijackthis, clean too. AVG AV, clean. Comodo AV, clean. SP2004 for dual core, 2 hours stress test and no bug. Memtest86 for 4 hours, no error at all. I got a 600w PSU which seems to be working fine according to my Mobo (volt is stable on all the positive voltages.)

Error codes I get :
Error code 1000008e
Error code 10000050
Error code 0000000a

All of which were checks and seem to be related to : RAM, PSU, Drivers.

I have updated windows to it's latest version and patched everything up to date(Yes, I OWN a legit CD with legit CDkey and all -.-). Video drivers were updated, audio drivers were updated.


-Bug triggers again?: The bug triggered again, I think (but may not be related). Was watching a movie on my PC when suddenly MPC (media player classic) crashed. (I am using CCCP codec pack). Restarted the movie and continued from where I left off with no problem, and then my PC rebooted after a little while.

Computer Specs:
Operating System Microsoft Windows XP Professional
OS Service Pack Service Pack 2
DirectX 4.09.00.0904 (DirectX 9.0c)
User Name Icemasta

Motherboard:
CPU Type Intel Pentium 4 530, 3054 MHz (15 x 204)
Motherboard Name Abit AA8-DuraMAX/AA8-3rd Eye (2 PCI, 3 PCI-E x1, 1 PCI-E x16, 4 DDR2 DIMM, Audio, Gigabit LAN, IEEE-1394)
Motherboard Chipset Intel Alderwood i925X
System Memory 1536 MB (DDR2-533 DDR2 SDRAM)
BIOS Type Award (06/25/04)
Communication Port Communications Port (COM1)
Communication Port ECP Printer Port (LPT1)

Display:
Video Adapter NVIDIA GeForce 7950 GT (256 MB)
Monitor Sampo AlphaScan 812S (000001)

Multimedia:
Audio Adapter Intel 82801FB ICH6 - High Definition Audio Controller [B-1]

 

[SOAD]

is it a possibility that the computer is overheating after being left on for a long time? (e.g. overnight) download speedfan from http://www.almico.com/sfdownload.php and post the temps you get after the pc has been on for a while.

 

[Elku]

As I said, I did a CPU stress test, meaning my CPUs were working at 100% for an hour, the temp didn't even get over 50 degree Celsius.
GPU card is even better, doesn't go up 35 degrees. Both have modded CPU fan.

 

[gbhall]

Weird and wonderful things CAN happen to hardware at VERY extended intervals - I remember a work PC crashing every few WEEKS that I eventually tracked to a faulty CD drive which was not ever in use, but disconnecting it cured the problem...

Simple things first, is there any chance of a power cut or brown-out during the night? I have no idea where in the World you are, and it can help if we are told.

Another - you say you have all power saving off, and all screen-saving off. Check 'wake-on' settings such as wake on modem ring etc. Make sure they are all off. Make sure sleep mode is diabled entirely. Check all application add-ons such as Java, Quicktime, other tings are not set to auto-update and are trying but failing at night.

All in all, a hardware fault is most likely.

 

[Elku]

Somehow, it didn't reboot at last night. Which means it's a possibility I fixed it in the many things I did yesterday. I'll see if it crashes tonight as well.

Simple things first, is there any chance of a power cut or brown-out during the night? I have no idea where in the World you are, and it can help if we are told.

I got an active UPS meaning it's basically impossible for my PC to run out of power (unless for extended power outages, of course).

Another - you say you have all power saving off, and all screen-saving off. Check 'wake-on' settings such as wake on modem ring etc. Make sure they are all off. Make sure sleep mode is diabled entirely. Check all application add-ons such as Java, Quicktime, other tings are not set to auto-update and are trying but failing at night.

This made me think. The firewall I used was "Comodo Firewall Pro", which in itself, is awesome. But it was an old version because the newest one required SP2 (which I didn't have 2 days ago , always sticked to SP1a). So I decided to update to SP2 yesterday and install the new firewall. Considering the firewall ALWAYS checks for update every 3 hours, and that old firewall could not be updated to the newest one, it could really cause a problem. Let's hope it's the cause of it! And thanks.

Still, it updated when I was active the PC many times and did not crash at that time, but it's a possibility.

 

[gbhall]

You probably fixed it. But just a word in your ear - on the whole here in the UK a UPS can be less reliable than the mains. After a year or two, the battery can get a bit stroppy, depends on the model.

I had a server at work that developed a merry habit of rebooting itself in the hour before dawn. Since nobody was around at the time, this was not easy to discover, and the server was still chugging along cheerfully. I just happened to notice the elapsed time was a few hours instead of hundreds of days (it's a Novell server, chuckle, you just set 'em and forget 'em, not like Windows, chuckle some more).
This went on for some time, could never catch it doing it, and eventually, at great expense, I changed the server power pack. Days later it did it again, during the day ! Great, it was the wacking great UPS all along, which never showed any sign of failure, always passed it's regular checks etc, etc, but a few days running without it soon proved the problem, and on taking the battery out - there was a nice puddle of acid.....

The moral is - never trust anything - even tests pass when they shouldn't. There is really only one final proof - component replacement.

Just one other thing that can trip people up (although you seem much more experienced than average), there is far too much software that for unknown and quite possibly programmer development only reasons, dumps regular log files in somewhat hidden places. Sometimes daily. After you get past a few thousand files all in the same folder, and even if there is still plenty of space on the drive, Windows will quite often get very, very upset and crash. Of course, you would probably find very good leads to this in the minidumps, so this is a more general observation for other readers with similar problems.

Hope your troubles are over, and do soon let us know if it was software all along. I try to keep a mental score of how many people find hardware rather than software at the root, and whether it is temperature-dependant.

 

[gbhall]

Thanks for that update. Full marks for letting us know.

 

[Elku]

Thanks for these advices. The next step was component testing piece by piece, but it got fixed before. As for my UPS, it's not even 3 months old, so I thought it would still be in good shape . They say you must change the battery once a year in the manual, although you can post-pone up to 3 years.