Core Temps advice

[fredthebest2003]

Im reading my core temps in RealTemp, and it looks as though my core 1 is sometimes as much as 5 degrees different from the other cores ... is this normal?

 

[fredthebest2003]

in case it helps, im overclocking my cpu right now, its an i5 750

oc settings are:

223x17 - 3.78Ghz

kept ram at 1333, its valueram, dont want to push it

ive got an arctic cooling freezer pro 7 rev 2

temps are 40 at idle, 60 at prime95 full whack. problem is usually, at idle, core 1 is like 41 and core 4 is about 36
same ratio at load, about 61 on core 1, 56 on core 4