I hope my answer can solve your worries

1. There are many factors of frequency loss, which may be caused by the conflict of graphics card drivers, unstable network and too many background programs after you restore, which may cause you to play games fluently.

2. After the computer is restored, you should press F8 to enter the safe mode to uninstall your graphics card driver, take out the CD that came with the computer to install the graphics card driver, and check your network speed and the number of background programs opened.

3. If you don't know much about computers, you can download a Tencent computer housekeeper directly.

Open Tencent Computer Manager-Toolbox-Hardware Detection-Install Driver (Reinstall your computer graphics card driver)

Open Tencent Computer Manager-Toolbox-Traffic Monitoring to see what software is taking up your network speed! Make your network speed not smooth enough, right-click to close

and open Tencent Computer Manager-clean up the garbage (because the system deposits too much garbage, which will also lead to the speed of your computer)

If you are not satisfied with my answer, you can continue to ask questions or make valuable suggestions, thank you!