Why does one core always run hotter than the other on my E6600?

According to Core Temp, one will be several degrees hotter at any given time.

That is normal. It's actually not normal to have them running at the same temperature! Some can differ up to 10c sometimes. Mine is ~7c

Remember when using a multi core CPU you do not utilize both cores equally unless you run dual Prime or Orthos, so it is quite normal, the higher temp core is probably the one that is more utilized, would not worry about this IMO.

As other's mentioned: Difference in core usage (loading), possibly in conjunction with some variance in sensor accuracy.

Nothing at all to be concerned over (not implying you were).

~ Strat ~

Yeah I just figured I'd step in here and be the twelfth person to say the exact same thing.

The difference is... well... you know...

And it's perfectly n... well... you know that too.

Yeah, I'm just popping back in to concur what rainless said!

One thing to consider when it comes to full load temps, in case its not clear, is that a BIG factor is that one core is wasting some cycles doing mundane crap like keeping system processes running, that can be less intensive "work" in a given cycle vs doing a FP calculation for Orthos etc, which causes the core doing system background crap to not heat as much because of those cycle changes. Also IHS contact etc can be a big factor in how the cores react. My Opty 165 went from a 5-7c difference to a 1-3c difference between cores when i lidded it.