1. Move files outside the system to other partitions; Uninstall the application software and games installed in partition C and reinstall them in other partitions. Second, turn off system restore. Right-click the computer on the desktop-Properties-Advanced System Settings-System Protection-Configuration-click "Turn off System Protection"-OK. Third, disable the hibernation function. Open the "Run" window, enter the "cmd" command and press enter, open the command prompt window, enter "powercfg -h off" and press enter. Fourth, move the virtual memory to other partitions. Right-click the desktop computer-Properties-Advanced System Settings-Advanced-Settings-Advanced-Change-click on drive C-select "No Paged File (n)"-"Settings", and the virtual memory in drive C will disappear; Then select drive D, select "Custom Size"-enter values in the following two text boxes of "Initial Size" and "Maximum Value"-Set-OK-restart. 5. Download the third-party software "Rubik's Cube" or "Win7 Optimizer" from the Internet, delete useless system files and clean up junk files.