I've been having this recently where the same core is routinely hotter than the others at idle. The 3rd core is always about 4-5 degrees hotter under low- moderate load. Under full load the temps even out over every core.
This is a 3 month old build and has only starting doing this in the past 2-3 weeks so it's started fairly recently. It is overclocked but is still using EIST/C1/C3 so thats a moot point at idle.
The temps are all still within acceptable ranges so I'm not overly concerned I'm just wondering if this is expected behaivour or whether I should be looking into it more. I don't think it's to do with affinity either as the workloads are usually pretty evenly spread amongst the cores from my observations.
Any ideas? Any other i5 users experienced the same?