There is provided a method for operating a basic input/output system (BIOS) of a pay-as-you go computer system. In one example embodiment, the method includes periodically resetting a watchdog timer, wherein failure to reset the watchdog timer indicates a security violation. In another example embodiment, the method also includes comparing a first time count representing motherboard use time with a second time count representing hard drive use time to determine if a security violation has occurred. There is also provided a pay-as-you-go computer system having a BIOS configured to determine if a hard drive is password protected. In an example embodiment, the BIOS is configured to calculate a password to unlock the hard drive if the hard drive is password protected.