Not "random restart", but "random shutdown"

[monkfish]

Hi all,

My pc will boot up ok and run perfectly, but shuts itself down after a random amount of time. I'll be sitting there writing an email, or ripping a cd, and boom! - it's shutdown. It happens that suddenly, like the power's been turned off at the mains or something. It doesn't automatically restart, either.

In terms of hardware changes, a new motherboard has recently been installed, but i am using the same cpu and heatsink cooler that formed the heart of a stable system in the past. However, since this old system was taken apart when the old motherboard went knees-up, i used the opportunity to wipe off the old thermal paste and apply some high-grade Zalman's paste. Both changes - the new mobo and the new thermal paste - were implemented at the same time.

Since then, this problem has developed.

If i try to switch it back on immediately after it has shut itself down, it'll get only so far into the boot sequence, and then shut down again. If i try to switch it back on after that, it'll shut down even earlier in the boot up process. It has to be left a couple of hours before it will succesfully boot up and can be used again.

I think it's a heating problem. I've added additional system fans, but they've made not the slightest difference.

If anyone has any ideas/experience/information that could help, i'd really appreciate it.

Thanks

monkfish

[sittas87]

HI Monkfish
Well firstly I'll suggest that you check you're event viewer after the shutdown to see if there's any leads witch might get you started.
This behaviour can be caused by a number of reasons, like hardware prob's to be specific.
Get back to me and we'll work on some leads.

[zeroth]

sittas is right...and it could also be a virus...you might want to post a HiJackThis log on the bug forum as well...

[monkfish]

HI Monkfish
Well firstly I'll suggest that you check you're event viewer after the shutdown to see if there's any leads witch might get you started.
This behaviour can be caused by a number of reasons, like hardware prob's to be specific.
Get back to me and we'll work on some leads.

Hi!

I've checked the event viewer, and it contains no mention of these crashes.

Just to be sure, i checked the "startup and recovery" settings in System Properties, and in case of system failure, the "write an event to the system log" box is ticked.

monkfish

[monkfish]

Hi!

After reading your suggestion, i tried running a complete system scan (i use AVG 8, btw), but it never had the chance to complete the scan - the computer shut down before it could finish.

I left it awhile and switched it back on, tried another scan, only for the same thing to happen again.

So it could well be a virus.

But i'm left wondering if the extra load on the cpu a full system scan entails could raise the cpu temperature enough to start causing problems :?:

monkfish

[zeroth]

why don't you see if you can download a monitor program like motherboard monitor - that will tell you what your fans are doing, the temp of the cpu, etc. - that is if you can get onto the internet long enough...

[monkfish]

Yikes!

Just after booting, the cpu temp registers around the 55 C mark, but steadily gets hotter and hotter.

After 10/20 minutes, surfing the net pushes the temp up to 65 C, and within the first 30 seconds of starting a complete system scan for viruses, it is 80 C, and still climbing. I stopped the scan before the computer turned itself down - that was after only 38 seconds, and the temp was in excess of 90 C!

That seems to be where the problem lies, now i just have to figure out what to do about it.

The fan on the cpu heatsink seems to be working (it's registering at over 2000 rpm) - it's not just doing anything about the heat!

The overall system temperature is 34 C, so that's not the problem, either.

[sittas87]

When last did you clean you're system and also apply some termal paste.

[monkfish]

I cleaned it all out and put fresh paste on when i changed my motherboard a couple of weeks ago - just before i started having this problem, as it happens.