Used laptop is behaving strangely. The reason is malware?

Question

Malware

Not so long ago I bought a used laptop in the service, they also installed Windows 10 there.
I began to notice that after 2-5 minutes after I leave it alone with me, the cooler starts to make noise. I sharply open the task manager, I see an instant drop in the load on the CPU from 75% to 4%.
Maybe when the system is idle, some services are running in the background? Or does it still look like some kind of malware?
Gentlemen, reading this, maybe you can tell me how to find this type of malware?

Answer 1

I began to notice that after 2-5 minutes after I leave it alone with me, the cooler starts to make noise.

Quiet with myself...
That's right - in windows 10, all service tasks run mainly in the background, when the computer is idle. As soon as the computer detects the fact of idle time, it immediately starts service tasks - for example, downloading updates, installing updates, defragmenting disks, etc.
If the user shows signs of activity, the system tries to slow down the tasks in progress, if possible.

Answer 2

https://free.drweb.ru/cureit

Answer 3

I had to test the hardware and install Windows myself right
now - only Live systems to find problems

Answer 4

Demolish this muck and install the system yourself. Check all the drivers and programs in startup yourself.
If the hardware and drivers allow, I generally recommend Windows 7.

Answer 5

autoruns by Sysinternals
Process Explorer by Sysinternals