I just assembled a new PC, and I've noticed that my CPU is idling at around 47-50°C, while my friend has the same setup and his CPU idles between 39-40°C. It's making me wonder what could be causing this temperature difference. Is there something I might have done wrong, or is this a common issue?
4 Answers
Ambient temperature can make a big difference! If your PCs are in different rooms, or if airflow around your PC is different, that could be why. Have you also checked to see how temperatures compare under full load? That’s a better way to gauge if there’s a big issue.
Sometimes, people use too much thermal paste, which can insulate rather than help cool. Make sure you’re using just a thin layer for good thermal contact. If you’ve done that and it’s still high, maybe consider reseating the cooler.
It could simply be that your cooling setup isn't as effective as your friend's. Even if everything looks identical, sometimes small differences in how the cooling system is mounted can affect temperatures. Double-check that everything is secured properly and seated well, and ensure that the cooler is making good contact with the CPU.
That’s within normal range for some CPUs, especially considering that different models can have varying thermal requirements. I have a higher-end CPU, and it idles around those temps too. Just keep an eye on it!

I haven’t benchmarked yet, but both our CPUs are R7 9700X.