My laptop heats up when...I'm not using it?

[7412]

I've noticed that, when I'm actively using my laptop, opening Chrome tabs or whatever, my laptop can stay completely quiet with no fans on for hours.

 

But oddly enough, when I let it open, with the screen on, but I'm doing nothing on it for a few minutes, it goes crazy, it starts to heat up and the fans turn on. 

How come NOT using my laptop somehow makes it heat up more than using it?

[VIVO-US]

It's probably background processes that wait for the computer to be idle.  There may be Windows updates installing, or an anti-virus program might be doing background scans.

 

If you want to find out for sure, set the screensaver and turning screen off to "never".  Bring up the task manager, set it to always sort by highest CPU usage, and then see what's happening once the computer is "idle".

[Eigenvektor]

Mine does this too. Afaik, this is caused by Windows doing clean up stuff when your computer has been idle for some time.

[Bombastinator]

Small tiny tiny possibility you’ve been botnetted and someone is trying to mine bitcoin with your box or something.  There are much more reasonable and likely answers already posted though.

[Silentprototipe]

Background processes, The simple act of waking up from sleep sends the CPU straight to 100% usage (R5 2500U here so wouldnt doubt thats happening to you) and thus fans start spinning hard on wake