Thermische diode calibreren

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Voor die-hard oc-ers die wel zich wel eens afvragen hoe nauwkeurig de cpu-temp werkelijk is, is dit interessante stukje op http://www.arcticsilver.com/diode_calibration.htm de moeite waard.
ik zal even quoten:

All modern Intel CPUs and the new AMD Palomino series CPUs have a thermal diode built in amongst the millions of transistors, capacitors, and resistors that comprise the actual core of the processor. Since this diode is right there in the middle of the action, it provides the most relevant CPU temperature readings. When you change the thermal compound or heatsink, the thermal diode will show the true effect of the change on the actual active part of the CPU that the cooling system is cooling. External measurements with thermocouples or thermistors will always be compromised by the thermal resistance of the heat path to the exterior device, the lack of an isothermal environment for the external device and thus the influence of the local environment. (case ambient temperature, motherboard temperature, airflow at the measuring location, etc.)
Unfortunately, very few motherboards incorporate the circuitry required to read the thermal diode and the diode/motherboard combination can display temperatures that are off by up to 6C or so from the actual temperature. This error is constant, so it does not affect the usefulness of the internal diode as a test device. A change to the cooling system that changes the temperature reading by 3C IS a 3C change regardless of whether the diode shows it as 43 to 40, or 38 to 35, or 40 to 37. The diode may lie, but it always tells the same lie.

But you can make it stop lying. There is a simple procedure for calibrating the internal diode on your motherboard---assuming you are lucky enough to have one of the motherboards capable of reading the diode---so that the CPU temperatures you see are the actual internal CPU temperatures.

The basis of this calibration is that a change in the speed of the CPU will cause a proportional change in the heat output of the CPU. So if we change the operating speed of the CPU by 50 percent the power dissipation of the CPU will also increase by 50 percent.