The question is quite straight-forward - how can i read CPU temperature under Windows?

Straight-forward it is, yet all the google gives is a long list of articles on T maintaining and reading programs.

Basically, is there some common way to get CPU temperature on x86 hardware? Specifically, under 32bit Windows XP/Vista? Some sort of system call will do too.

I can think of two methods. First, you motherboard likely came with some utilities that allow you to monitor CPU temps, MB temps, fan speeds, etc.

Second, you can view that information in BIOS (hit F2, Del, Esc, etc. - MB specific - to get to "set-up").

Okay, more precisely:
How can i make a program, that will find out CPU temperature, under Win XP/Vista?

google for MSR (Model Specific Registers) DTS (Digital Termal Sensor) & Temperature.

Oh, sorry Artlav. I should have read your post more carefully.

You can try Win32_TemperatureProbe Class.

While you can use the IA32_THERM_STATUS MSR, you'll have to know in advance the specific processor TCC activation temperature because the digital reading from the sensor using this MSR is a value relative to the processor's TCC activation temperature. I think that would be a pain in the ass making it a generic program that is processor independent. The processor's TCC activation temperature is found in the processor's specification data sheet.

As far that I know it depends on how you're intending on reading it and where from. You could read it from an integrated sensor on the Motherboard (Usually innacuratte), or maybe from a diode in the Processor itself (Like CoreTemp does for AMD K8 based Processors for example). Either way should requiere specific knowledge on either a Motherboard or Chipset series or the Processor, so there shouldn't be an universal way to read it with the exeption that maybe there is a generic or standarized BIOS call, but you wouldn't be reading it from the sensors directly.