This is a hardware question, not specifically Linux, so if this is the wrong forum please suggest a better place to post it.

I've just acquired a computer with an AMD Athlon XP 2600+ processor. It's much faster than my previous computer.
It has a little device (Fan Mate 1) inside with a knob that controls the speed of the CPU fan. I've turned the fan speed down to make the computer quieter.

The BIOS reports that the CPU temp is now 64 degrees C.
The AMD web site says not to let the CPU run hotter than 85 degrees C.

Is there any reason why I wouldn't want the CPU to run up to, say, 70 - 80 degrees C, as long as it doesn't exceed 85 degrees?

Is there something like a "cruising temperature" range that it is a good idea to stay within?

Thank you,
- TSloth

You might get a lot of different opinions here, but I wouldn't want my CPU running over 45 degrees Celsius. The cooler it is, the longer it will last. Excessive heat shortens the life of the processor and can cause lockups, reboots,etc.

If your fan is really noisy, you might consider replacing it rather than turning it down.

my laptop automatically shuts off after 70 degrees C. Im curious why you wanted it to run hotter then it already is - is the fan still too noisey and you planned on turning it down some more? I know the cooler it runs the better. Im curious how cool you can run a processor. Is there such a thing as running it too cold?

Yeah, if you get it to -273 C, then all motion of particles would cease, hence no electricity

Assume that the absolute maximum working temperature of the semiconductor material inside the processor will be around 150C. Get beyond that, and your processor is dead. But, there are variables involved here - the nature of the temperature measuring device springs to mind.. Is it within the processor package, or located on the mainboard (whereupon there will be thermal resistances to consider, etc.)..

But the other thing to consider is that if you're looking at the BIOS screen, the processor will be practically idling. If you start doing some real, CPU intensive work, the temperature will rise. I've seen this on a passively cooled Via EPIA board - and I saw rises of 20C or more with the processor under load.

You might want to look into the lmsensors package and see if you can do some 'real-time' measurements of your own.

My advice would be to adhere rigidly to AMD's specs, and remember that the hotter you run the processor, the shorter its life (and we're talking exponentially here!)

My experience with a couple of AMD Athlon XP 3200s is that the temperature depends a lot on the specific heatsink/fan used and on whether you are using the standard thermal transfer material that comes with many heatsinks or whether you are using thermal grease.

The lowest and highest idle temperatures I have seen in a 25 degree C room are 46 and 60 degrees, respectively. Both of these were seen on the same system, with the original CPU/heatsink purchased as a boxed set giving the high temperature and with a better quality heatsink installed with thermal grease giving the lower temperature. I went through 4 heatsinks before I found one I liked, which was the Cooler Master XDream 2. It's very quiet.

Given the sharp temperature rise under load, I was not happy with the 60 degree starting point, hence the search for a better heatsink.

Good heatsinks for the Athlon XP are fairly cheap (less than US$25), so why put up with one that runs hot? The Cooler Master XDream 2 currently sells for US$9.00 at Sundial Micro: http://www.sundialmicro.com/cooler_m..._1738_193.html

There are some newer Cooler Masters for a few more $$$ worth looking at: http://www.sundialmicro.com/Intel-37...lers_1738.html and I'm not talking about the liquid cooled ones, which are an overkill, unless you plan to do some extreme overclocking.

Thank you each for your very informative answers.
I will get a quieter fan (probably one of the Cooler Masters) and lower the temperature.

- TSloth

... and be sure to use thermal grease!