Have you ever tied to change the power settings?
First open the power settings, then click "change plan settings" beside the "balanced (recommended)" option. Then click "change advanced power settings" on the screen that appears. In the dialog box, scroll down and expand "Multimedia settings". Change the "plugged in" option to balanced.
Otherwise try to change the power states of the cpu, and see if it works.
You can also just check out the top 10 [https://www.minitool.com/partition-disk/my-computer-lags.html#10-reasons-for-pc-lagging-and-how-to-fix-stop-lag-windows-10/8/7-210|reasons for a lagging computer].