Computer Troubleshooting

REISUB is a safe way to reboot a frozen Linux system, allowing you to restart without file system corruption. It acts as the linux version of 'Ctrl + Alt + Del' on windows.

Hold Alt and SysRq (Print Screen). While holding them, press R, then E, then I, then S, then U, then B. Wait about one second between each key.

Print Screen/SysRq on a standard english keyboard

Print screen key on keyboard
By User:Stannered - Modification of Image:Qwerty.svg, CC BY-SA 3.0, Link

Use this only when the system is frozen. On laptops you may need Fn with Alt and SysRq.