CPU heat sensor -- kaput?

Got a computer problem, first of all here’s the specs: P3/450, 384mb ram, Win98SE.

Ever since last June I’ve had an overheating problem with my CPU, which I posted about in this thread. Since then, I’ve been monitoring the temp very closely, which has been in the range of 65-75C – a bit high, but there wasn’t much I could do except watch it and keep the vents clean.

Today, I did a routine cleaning and had to pull the CPU to clean the fan/heat sink (as best I could, anyway) but when I put it all back together, the temp shot up to an unbelievable 100C!!! So I shut down & waited about four hours, and now when I start up it shows an INITIAL temp of about 75C/167F, and that’s like 20 seconds after hitting the power button.

So…I guess the heat sensor must be busted. In fact I’m wondering if my problem last year was even a problem. :slight_smile: So my question for the computer gurus here is…what now? Is it a good idea to keep running my computer 24/7 like I have been all this time? Speedfan’s registering a temp of 102C right now, and I had to disable the temp monitor in CMOS because it kept beeping at me otherwise…but other than that, no problems at all, not even during the last nine months. (Aside from normal Windoze crashes & all that…)

Hoping to hear some good news…

Well, I’m not an expert but I have had an overheating problem.

The temp sensors installed on motherboards are notoriously unreliable. Upgrading your BIOS can drop the temps by 10 deg C or more.

In my case, I was experiencing weird faults and random restarts. The fix (which was simple and cheap) was to clean my fan/heatsink unit. Enough dust had accumulated that a simple cleaning dropped my temps by 15 deg C.

If you want to see if you have a temp problem you might want to run Prime 95 for a while. You can download the client and then run the “stress test” without actually involving yourself in the search for a prime number. This test has become a de-facto standard for stress-testing CPUs (well, at least for people dealing with temperature issues).

If you can run Prime 95 without any problems then I would say that you do not have an overheat problem at all but a sensing problem. When I had my actual overheat problem my machine would hit the auto-shutdown temp limit in about a minute. Prime 95 will also (IIRC) detect faulty calculations which could be caused by a CPU running very hot.

Good luck!