Dell PowerEdge M620 Owner's Manual page 154

As you type, placeholders appear in the field.
The password assignment is not case-sensitive. Certain key combinations are
invalid and if you enter one, the system beeps. To erase a character, press
<Backspace> or the left-arrow key.
When you verify the password, the Setup Password changes to Enabled. The
next time you enter the System Setup program, the system prompts you for
the setup password.
A change to the Setup Password option becomes effective immediately
(restarting the system is not required).
Operating With a Setup Password Enabled
If Setup Password is Enabled, you must enter the correct setup password
before modifying most of the System Setup options.
If you do not enter the correct password in three attempts, the system lets you
view, but not modify, the System Setup screens. The following options are
exceptions: If System Password is not Enabled and is not locked through the
Password Status option, you can assign a system password. You cannot disable
or change an existing system password.
NOTE:
You can use the Password Status option in conjunction with the Setup
Password option to protect the system password from unauthorized changes.
Deleting or Changing an Existing Setup Password
1 Enter the System Setup program and select the System Security.
2 Highlight Setup Password, press <Enter> to access the setup password
window. Press <Enter> twice to clear the existing setup password.
The setting changes to Not Enabled.
3 If you want to assign a new setup password, perform the steps in "Assigning
a Setup Password" on page 153.
154
Using the System Setup Program and UEFI Boot Manager