IBM PASSWORD INFORMATION:
In the IBM Notebook Computer world forgetting the computer password (making the computer unusable). As many as three passwords may be needed for any ThinkPad computer: the power-on password (POP), the hard-disk password (HDP), and the supervisor password (SVP). If any of these passwords have been set, a prompt for it appears on the screen whenever the computer is turned on. The computer does not start until the password is entered.
Exception: If only an SVP is installed, the password prompt doesn’t appear when the operating system is booted.

Power-on password:
A power-on password (POP) protects the system from Being powered on by an unauthorized person. The password must be entered before an operating system can be booted.
Normal Operation -When the power-on password has been set, a prompt will appear during the system start up, and the power-on password must be entered before an operating system can be booted.

Hard-disk password:
There are two hard-disk passwords (HDPs): User HDP—for the user, Master HDP—for the system administrator, who can use it to get access to the hard disk even if the user has changed the user HDP Note: There are two modes for the HDP: User only and Master + User. The Master + User mode requires two HDPs; the system administrator enters both in the same operation. The system administrator then provides the user HDP to the system user. Attention If the user HDP has been forgotten, check whether a master HDP has been set. It it has, it can be used for access to the hard-disk drive. If no master HDP is available, IBM does not provide any services to reset either the user or the master HDP, or to recover data from the hard-disk drive. The hard-disk drive can be replaced for a scheduled fee.
Normal Operation -There are two modes for the hard drive password: user only and master + user. The master + user mode requires two hard drive passwords; the system administrator enters both in the same operation and provides the user hard drive password to the system user. If either either master + user or user only are set, a the password prompt will appear during the boot process either the master or the user hard drive password will need to be entered before the operating system can be booted.

Supervisor password:
A supervisor password (SVP) protects the system information stored in the IBM BIOS Setup Utility. The SVP must be entered in order to get access to the IBM BIOS Setup Utility and make changes to system configuration settings. Attention If the SVP has been forgotten and cannot be made available to the servicer, there is no service procedure to reset the password. The systemboard must be replaced for a scheduled fee.

Normal operation -When the supervisor password is set, then a prompt will appear when entering the ThinkPad BIOS setup utility and the supervisor password will need to be entered before access will be granted to view or change settings.
Note: Setting the supervisor password does not prevent access to the operating system. If the hard drive password and power-on password are not set, then setting a supervisor password will not cause the password prompt to appear when the operating system is booted.
AND ONCE MORE AGAIN..... Forgotten supervisor password .A forgotten supervisor password will prevent access to the ThinkPad BIOS setup utility. To regain access the system will need to be serviced to have the system board and hard drive replaced. Proof of purchase is required, and this repair is not covered under the warranty.