CPU temp's on core 2 duo, should they be significantly different?

Josh Carroll josh.carroll at gmail.com
Mon Jun 23 19:18:21 UTC 2008

> I've noticed that cpu.0 is consistently hotter than cpu.1, even on an
> unloaded machine.  Is that because that core's doing housekeeping work
> whilst the other is truly idle?
> dev.cpu.0.temperature: 44
> dev.cpu.1.temperature: 29

I notice some differences on my quad-core (Q6600) CPU, too:

dev.cpu.0.temperature: 35
dev.cpu.1.temperature: 34
dev.cpu.2.temperature: 27
dev.cpu.3.temperature: 30

The differences also stay around the same when I yes > /dev/null 4
times to load up each core:

dev.cpu.0.temperature: 47
dev.cpu.1.temperature: 45
dev.cpu.2.temperature: 38
dev.cpu.3.temperature: 42

The discrepancy isn't as much as in your case, though. 15 C is pretty
significant. It could be that either your heat spreader or heat sink
are concave or convex causing one of the cores to get hotter.

On my dual-core box, here are the idle temps:

dev.cpu.0.temperature: 33
dev.cpu.1.temperature: 31

and under load:

dev.cpu.0.temperature: 48
dev.cpu.1.temperature: 46

I'd recommend taking the heat sink off and seeing how the thermal
grease is spread on the CPU's head spreader and on the heatsink
itself. If it looks lopsided or extremely thick on one side of the CPU
package or extremely thin (to the point where you can still see the
sheen of the heatsink or heat spreader), then re-mount the heatsink
and try to make sure it's evenly distributing the pressure down on the
CPU package.


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