Click Next in the Performance window to continue.

Type msdt.exe /id PerformanceDiagnostic and press the Enter button.

Right click on Command Prompt and choose Run as administrator.

Check Adjust for best performance in Performance Options window.

Click the Adjust the appearance and performance of Windows link under System.

Type performance into the search box at the upper right.

Select None from the drop-down list of Screen saver.

Look for the Screen saver settings option in the right panel and click on it.

Type lock screen settings and press Enter on the keyboard.

Press Windows + S to open Windows Search.

Start changing Background picture, Colors, Lock screen background and Themes and see what happens.

(You can also replace above steps by right clicking on the blank area on desktop and choosing Personalize.) Select Personalization from the window.Choose Settings (looks like a gear) from the left sidebar of the menu.Click on the Window logo button in the lower left corner of your Screen.One function of Desktop Window Manager is managing desktop utilization so if the wallpaper or theme you’re using currently is taking too many resources, you should change it. How to fix Desktop Window Manager high CPU or high memory on Windows 10? Fix Desktop Window Manager High CPU (DWM.exe)

Microsoft window manager