I have recently installed a new heat sink & fan combination on my Core 2 Quad since my CPU was hitting about 70C under load. This has managed reduce temperatures while running Prime95 to about 54C, which I'm taking as a win (this is ~30 minutes after fitting).

I'm a little confused though. The temperature readings given above are for CORE temperatures, but HWMonitor is showing a 5th "CPU" temperature (4 temperatures being the individual core temps) which is showing 21C idle, when idle temperatures for the cores vary between 37C and 42C.

I guess there are two questions here:

  1. Are my CPU/Core temperatures decent, and is it safe to overclock when these are stock clock temperatures?
  2. I gather that the maximum safe operating temperature for a C2Q is ~70C, so which temperature should I measure against, the core temperatures (which are higher), or the CPU temperature reading?
  • The CPU temperature is the actual temperature of the whole CPU as measured (usually) from underneath it by a sensor on the motherboard.
    – Majenko
    Mar 19, 2011 at 23:56
  • Which particular CPU do you have? 70 degrees sounds low for a maximum.
    – user3463
    Mar 20, 2011 at 5:35
  • @Randolph Potter - Core 2 Quad Q9450 Revision C1. Mar 20, 2011 at 19:13

1 Answer 1


From my understanding 70C is maximum stable temp which you don't want to be near on a regular basis it will kill the chip faster... keeping it around 60C-65C is safe. Read this for more detail http://www.yougamers.com/forum/showthread.php?t=82284 use CPUz to get the information about your cpu to compare to the posters finding... i.e. the processor model/stepping

  • the link seems to be dead. where can I find more details?
    – Federico
    Jun 8, 2018 at 11:48

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.