laptop shutting itself down

I've got an HP dv8339us laptop running WinXP MCE SP3 that is shutting itself down occasionally. I ran memtest86 for 8 hours, and a disk exercise utility for a few hours, and had no problems. But when I run Prime95 (a cpu stress test), it shuts down in 10-20 minutes.

Temperatures reach about 95C before shutdown. I can reboot the laptop immediately and it has no issues.

However... if I run Prime95 in safe mode, or off of a Bart PE boot disk, temperatures never get above 67C, and it will run the stress test forever!

I updated the BIOS to the newest version, and reinstalled the motherboard drivers (including smbus). Neither helped.

What is going on?

 

I think you've answered this yourself. The PC is overheating. If you stop running Prime95 and just use the PC as you would normally, how does it run? The reason the PC runs cooler with Prime95 in safe mode is because you're in safe mode. This means the PC is running on a bare minimum of drivers and services and the PC does not work as hard, therefore the temps are lower.

 

The reason I'm trying to diagnose this is because it shuts down by itself occassionally. It's happened during virus scans, defrags, rendering, etc. I'm not sure I agree with your logic regarding safe mode. Prime95 will take both cores up to 100% regardless of what services are running.

 

try to reformat your laptop, it might help!!!!juz try!

 

your answer to reformat doesn't seem to help in this situation, nor in the other post(s) that you've made...


as for the problem, yes, your laptop is overheating, probably from the combination of video card along with cpu heat. In safe mode, you are running without 3d capable drivers, so you aren't getting that extra heat in there. 95 is a bit hot. I know laptops get warm. mine has been to 90 before, but only while heavy gaming in the summertime.

 

I considered the fact that the video card would be adding to the heat, so I disabled the video card drivers, which resulted in the resolution defaulting to 640x480. It did not seem to make any noticeable difference in temperature.