I have a zalman 9500 cpu cooler. I can physically measure the temperature at the base of the heatsink (The part that sits directly on top of the cpu).

Let's assume it has been seated correctly.

I'm wondering, how much difference, typically, would there be, between "this" reading and temperature the cpu itself is running at (like numbers reported from various monitoring software, MB monitor, sensors on the core etc.) I understand the temperature changes of my reading will be less responsive than perhaps the sensors on the core, but lets assume constant load, and it has been running for a fair amount of time for everything to equalize.

Any ideas? I've been googling this for awhile, cannot seem to get any clear answer.

I'm confused as to what your actually asking. You just want to know the average temp difference between the CPU core or case and the heat sink?

I would think that if your CPU cooler is properly mounted than what ever the difference between your sink temp (laser temp device?) and what the BIOS reports is your answer.

Maybe thermal compound used would alter the average, as would CPU type (C2, heatium 4, Athlon).

Are you trying to decided if your cooler is working sufficiently?

I'm interested to know the difference between the base of the heat sink to "Any" of the on board sensors that you monitor with software like coretemp or whatever.

"I would think that if your CPU cooler is properly mounted than what ever the difference between your sink temp (laser temp device?) and what the BIOS reports is your answer. "

Yep, I can obtain this on my machine, but I'm interesting in what the 'typical' is, in other words, what type of numbers are other people getting. [Not to mention I have E8500, and the monitor software readings are all over the place.]

Well one of the reason is because there is this fan controller display unit that came with the case I have. It has a few temperature probes. There is this alarm function on it I would like to utilize. So I have to set what temperature it should "start beeping". So, I want to know what the correlation between something I can measure with my temperature probe vs. the onboard sensor cpu uses to do the throttling and such. In example, IF** the cores run 15 degrees hotter, I would set the alarm to go off.. say (70-15) 55 degrees.

That makes more sense. If I had a laser temp guage I'd help you out.

Are you planning on putting the probe on the heat sink, and not under it?