In Task Manager have a look under the Processes Tab to see what is using most of the CPU - you can ignore System Idle Process, which should be somewhere in the High 90's %.
Also a good idea to run scans with SuperAntiSpyware and Malwarebytes.
Samsung Galaxy S9 review
Wacom Cintiq Pro 24 and 32 review – hands-on
When is the next Apple event?
Qu’est-ce qu’Amazon Prime ?