Reinstalling a system at a hardware and software level is a pretty interesting rite of passage. I'm taking baseline measurements for temperature levels and fan speeds and all that good stuff. Finding out that a quad core technically has 5 different places you can read temperatures from is kind of interesting. Interesting in the way which doesn't actually help me at all in any way shape or form. Through the course of a few BIOS updates, and utility installations I've had some varying temperatures, combined with some worrying amounts of noise.
Fortunately, I realised pretty quickly that by default my insanely huge Zalman CPU fan runs at 100% speed. It seems it can safely run at about 30-40% speed in order to keep my system cooled when idling, and 60-70% under load is suitable. That sorts out most of the noise issues.
While I'm not too keen on relying on it,
Speedfan was a pretty useful part of this process. I've seen it used in the Startup folder which seemed incredibly flaky. For me, I used it to play about with different fan speed combinations in order to find the right levels of noise to cooling. It's a pretty useful utility, even if some of it's temperature readings seem to come from rather bizarre places.
Oh, and it runs on 64 bit operating systems too! :)