CPU Heating question

Hi,

Here's my setup:

P5Q - Pro (Bios 1306)
E8500 - 3.16 GHz
Zalman 9500A
Radeon 4870
G.Skill F2-6400CL5D-4GBPQ
ENERMAX MODU82+ EMD625AWT

My question relates to my CPU. In Speedfan, CPU reading and Core temps are regularly 15 degrees off (right now, CPU is 32C and Core is 47C). I am also wondering why there would be such high temperatures on the cpu when I am using the Zalman heatsink. Is it something about being seated incorrectly or not enough thermal paste? EDIT: I reseated it/reapplied thermal paste. That helped. My mobo temp is still a bit high, though.

Also, there are ... somewhat regular spikes (that don't seem to happen) where the CPU in speedfan jumps to 120C. I turn it off, touch the CPU and it isn't uncomfortably hot or anything. I check the BIOS and it's around normal (about 33-40C) and then on restart, everything is fine. Is it just a bad thermal sensor?

Here is an updated screenshot



Thanks for all your help and I again apologize if this has been answered 100's of times.