The
key lock
on the front of the system unit allows you to lock your PC. If your PC is
locked, it will not
boot.
This is great protection, if your PC is in an open area and accessible to
different people.
If you use this feature of your PC, be careful not to lose the key. It is
very difficult to get a new one. However, it is possible to bypass this
feature by disconnecting it from inside the system unit.