ill-behaved program caused CPU to spike to 95C

Although I'm not new to the forum, this is my first post. I recently built a computer (see sig) with the specific objective of reducing system noise. I selected my components accordingly and use SpeedFan to monitor temps and manage fans. CPU core temp generally hovers around 34C (I'm not into gaming or OC'ing). TCaseMax is 65C for my CPU.

There's one application I use that isn't very well behaved. Originally a DOS application, it was eventually converted to Windows. It's one of the few programs I use that push my CPU core temp into the 40C to 45C range, still well within limits.

This morning when I closed the program, it seemed to lock up for a few seconds befor shutting down, and SpeedFan immediately beeped a CPU temperature warning. I checked the core temp log and SPeedFan recorded a momentary spike of 95C !!

It would be easy to conclude I need to get rid of the program, but what happened doesn't make sense to me. For example, when I run AVG virus scan, both cores remain at or near 100% capacity for more than a half hour and core temp remains below 45C (even with fans running at reduced RPMs). If prolonged use of CPU at 100% doesn't push the core temp, then what in the world could this program have done to cause a 95C spike?!

I'm just taking a guess here, but I think that old program must have interfered with Speedfan in some way and either gave you a false reading or if you are using Speedfan to control the fan speeds it caused Speedfan to stop the cpu fan somehow. Try running something like Prime95 and see where your temps peak out at. If Prime95 can't get the temps close to 95 C then that old program shouldn't be able to either unless it is stopping the cpu fan somehow.

I'm with mud in the fact that if running 100% load on all your cores can't get your temps above 50C, there's no way your CPU hit 95C unless it messed with the fan speed. Even then it would have had to turn it off. More than likely it was a false reading. Given that speedfan beeped after a lockup tells me that it was just a glitch in the system. Your CPU won't go from 40C to 95C instanteously.

Axis

Thanks for your replies. The fans didn't turn off. In fact, they immediately went to 100%. Also, this all happened within a couple of seconds. If I manually turn all my fans off, the core temp will climb, but not so suddenly.

The false reading seems plausible, especially considering that the CPU socket temp reading didn't spike. Normally the core temp and socket temp roughly track together.

If I'm able to replicate the lock-up (so far, no luck), I would like to try a different monitoring program. I have CoreTemp but it doesn't keep a log. What about Prime95, does it generate a log or graph?

ginahoy, Core Temp does create a log, but you have to enable that under the Options/Settings menu. You can also change the default settings on the log too in there.

muddocktor said:

ginahoy, Core Temp does create a log, but you have to enable that under the Options/Settings menu. You can also change the default settings on the log too in there.

Click to expand...

Didn't realize that about Core Temp... thanks! The log function, though not graphical, is better than SpeedFan because it tracks both cores as well as the low-high range between readings, and also correlates to CPU load. Awesome!