Is it normal for a CPU to be always be cooler than 30 degrees?

Everytime I measure the temperature of my CPU (Core i5 3570K) using the "acpi -t" command under GNU/Linux I get the same output:

Thermal 0: ok, 29.8 degrees C
Thermal 1: ok, 27.8 degrees C

While I do use a decent CPU cooler this still seems somewhat low to me. Is the temperature o.k. or do I have to fear some serious problems (like the CPU not throttling even when being hot)?

EDIT: My concerns aren't whether the temparature is ok but whether the sensor(s) could be damaged. I am sorry for not making this clear.

3 Answers

If you have a good cooler then 30 C is not too uncommon of a temperature if the computer is idling. The real issue is seeing how your system runs under load. Try running it under stress and see what temperatures you get.

You can never have your CPU too cold. The colder the better. 29 degrees C is a good temp. You really only have to worry once it gets too hot (typically 90+ degrees C, but it depends on your processor).

However, given the new circumstances it sure sounds like a sensor failure.

I just installed this CPU in my computer, and I was getting exactly the same temperatures as yours. First, the i5-3570K is quadcore, and second I found out that these reported temperatures do not change with load as they should be. So I figured these reported temperatures were bunk. After running sensors-detect, I found the following worked to fix temperature reporting. Following lines must be added to /etc/modules:

# Generated by sensors-detect on Sun Jul 15 12:26:02 2012
# Chip drivers
coretemp

I then rebooted, then installed the "Hardware Sensors Monitor" to my toolbar, which now correctly report 4 temperatures, which rise and fall according to CPU load. At idle, I currently get 33C average for all cores, ambient temperature is 25C.