Thread: Acurate temps
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Old 23rd July, 2008, 10:31 AM
Aedan Aedan is offline
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Join Date: September 2001
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It could also depend on which temperature sensors they're reading. Core 2 Duo processors have multiple sensors. One of which reads the temperature of the heat spreader, and two read the junction temperature internal to the chip. (Core 2 quad processors have one case, and four junction sensors). Speedfan can measure both the case and junction temperatures.

To further confuse things, the heatspreader sensor is analog and is converted by components on the motherboard. Changing motherboard can change the reading on the heatspreader. The junction sensors are converted inside the CPU, and are factory calibrated to about +/- 1C. This means that moving the CPU from one motherboard to another will still result in repeatable junction temperatures.

So, what you're seeing with HW is the heatspreader sensor. SF looks like it's currently giving you one of the junction temperatures. The junction temperatures are what you want to be watching.

Last edited by Áedán; 23rd July, 2008 at 10:32 AM.
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