Open the computer cover.
Remove the jumper plug from the PSWD jumper to disable the password feature.
See "Jumper Settings" to locate the password jumper (labeled "PSWD") on the system board.
Close the computer cover.
Reconnect your computer and devices to an electrical outlet, and then turn them on.
This erases the existing password(s).
Enter system setup and verify that the password is disabled. Proceed to step 6 if you want to assign a new password.
NOTE: Before you assign a new system and/or setup password, you must replace the PSWD jumper plug to reenable the password feature.
CAUTION: Before you open the computer cover, see "Safety Instructions."
http://support.dell.com/support/edocs/systems/opgx50/ena/ug/safeinfo.htm#1106388
