Why is CPU 0 always 3C cooler than CPU 1?

I saw a potential answer to this in a thread a while back but I couldn't find it and I really want to know why core 0 on my C2D 6600 is consistently 2-3 degrees cooler than core 1.

Doesn't matter what HSF or thermal compound is used or how its used core 1 is always hotter.

Funny...on my E6600 CPU 0 was always a few degrees warmer than CPU 1. But now on my X6800 CPU 0 is the cooler one.

The only answer I can figure from reading threads is that they are seperate cores and it would be impossible for them to be exactly the same in any regards.

Maybe someone will explain it to both of us a little better.

yeah mine always runs 3c hotter on core 1

hrm...interesting that core 0 was hotter for you on that particular machine..

at least i'm not alone, would suck to be 'that guy whose cores don't run at the same temps'

Is that the core that the OS defaults to run on?

Physically they're not the same cores, so you can't expect them to have the same temperature; un-perfect construction means one core will have better thermal interface than the other. It also means that one core will often perform slightly better than the other (Like you may notice that one core ALWAYS errors out before the other in Orthos).
Chance is a factor in determining whether the CPU you buy is physically a better product. Building CPUs and other electronic devices is really, really complicated, so you can't really complain.

Note: For me, Core0 is ~3*C hotter than Core1.