A raw CPU temp may or may not have much meaning (beyond whether or not it is in the safe operating temperature zone) due to the configuration of the system.
For instance, it might sound impressive for me to tell you that my CPU idles at around 30°. But it's not by magic.
At 20 - 22° C ambient, my AMD Phenom II x6 1100T idles at 19 - 21° per AMD's goofy temperature output as interpreted by sensors. I add 10° via a script to feed to my conky for a corrected reading of 29 - 31°.
It's air cooled by a Noctua NH-D14, voltage regulated fan speed (because Noctua's fans that came with it when I bought it are not PWM), with the fans running ~ 500 - 525 rpm (max is 1200). The machine is in a Cooler Master HAF X case with 4 200mm fans.
Running pi on all six cores for 30 minutes gives me a stable temperature of 50°C +/-1° at 100% core load. I've never seen the CPU cooling fans kick up above 1000 rpm (83% of 1200 rpm).
The reason the CPU runs as cool as it does is that I'm blowing massive amounts of cool air over it.
Right now, with several things running, sensors is giving me this on the CPU:
k10temp-pci-00c3
Adapter: PCI adapter
temp1: +22.2°C
My conky shows this:
[ATTACH=CONFIG]246117[/ATTACH]