Wide temp difference betwen cores

Hello,

I have a Q9400 and I installed a S1283 HSF. The first attempt I think I did not tighten the HSF enough - idle temps were 50-62C and load temps were 82 - 89C. I reinstalled the HSF and tightened it enough this time and the temps are much better.

Core 0: 41 C
Core 1: 22 C = room temperature.
Core 2: 37 C
Core 3: 37 C

Before I reinstalled the HSF, the temperatures were much closer together.

I am using Speedfan to get the temps, and I used SiSoftware Sandra's CPU benchmark to max out the cores for a minute or so. The temps did not budge after running the benchmark.

If these temps are correct, is a 19 degree difference between Core 0 and Core 1 a problem? Should I reinstall the HSF again to get more even temperatures or will the CPU be fine as it is?

Thank you.