To convert the numbers in my post to fahrenheit:
- Celsius temperature by 9.
- Divide the answer by 5.
- Add 32.
Usually, an Intel CPU is best below 40*C.
40-50*C is still okay though a little hot, 50-60*C is what I considered to be the maximum "good working" temperature. If you go over 60*C, then you'd probably want to look into better cooling ASAP before something goes wrong!