Some Dell OptiPlex desktops have a "PSWD" jumper on the motherboard. Removing this jumper during boot disables password checking. Check your specific Dell service manual.
The number displayed is not the password itself. It is an error code generated by the system's algorithm based on the Service Tag (Serial Number) of the computer. This code is often referred to as the "Hint Number" because it provides the necessary clue for a technician or a master key generator to calculate the unlock password. Dell Bios Password Unlock Key Hint Number
To find the unlock key hint number, follow these steps: Some Dell OptiPlex desktops have a "PSWD" jumper
When you enter the wrong BIOS password three times on most Dell systems (Latitude, Precision, OptiPlex, XPS, and some Inspirons), the system doesn't just say "Wrong Password." Instead, it enters a "lockout mode" and displays a unique code: the (often called the Service Tag Hash, System Disabled Code, or A code). The number displayed is not the password itself
In Dell support forums, users call it the or "Service Tag Hash."
No. The password is stored in the BIOS flash chip on the motherboard, not on the hard drive. Removing the HDD has no effect.