Basically the problem is simple. My i3-9100f keeps working at 100% during gaming (Watch Dogs 2, AS Odyssey Division 2). I believe that might be the reason why my PC is underperforming (over 10-20% loss of performance comparing to Youtube's game benchmarks)
Intel Core i3-9100f
8GB RAM DDR4 2133MHz (OC to 2400MHz) Single Channel
Asus RX 580 4GB
ASRock H310M
Windows 10 Pro
SSD Crucial MX500 250GB and Sandisk 250GB
Intel Core i3-9100f
8GB RAM DDR4 2133MHz (OC to 2400MHz) Single Channel
Asus RX 580 4GB
ASRock H310M
Windows 10 Pro
SSD Crucial MX500 250GB and Sandisk 250GB