[Solved] Stock e7500 temps and voltages

Yesterday I picked a boxed e7500 and MSI p43 neo-f. Installation was very smooth. Bios reports temps of 31c/28c, exactly what I was expecting/hoping for.

When I get into windows, I launch coretemp (0.99.5) which reported temps of 41/37 at idle (1.604g / 1.152 vcore). Same with real temp (3.00). The temps never fluctuate at idle (between 0 and 15% load) so I take it that something about the programs don't allow it to report temperatures below a certain value. So whatever, I'll take the BIOS's temp as the actual.

However, when I run prime95 the temps skyrocket. I'm getting high temps of 63/58. Ambient temp is 18 so we're talking about an increase of over 40c. By contrast, my old phenom x3 8450 never went above 31 at load.

So my question is: are these temps to be expected? Is it safe to trust temps given by software like core temp and real temp?

I was hoping I could do a mild overclock to about 3.4 without buying a new cooler, but these temps are already out of my comfort zone. Any advice or insights would help a lot.