That is to say, there is no default master password on all Dell systems. It's generated from a series of numbers which will be obtained by a support professional when you call them and give proof of ownership (copy of invoice or other confirmation usually is enough, varies). When you've supplied this information the L1 escalates the case and gives you a callback as soon as he has the master password with instructions on how to reset password.
What was posted above is true with a forgotten, lost or un-known password.
However, there is a "Default" Password and that is a blank (empty) password box, if a password had never never been 'set', you just hit enter [ ] on the blank password request screen and you will be allowed access.
Default password on DOS or Windows systems would be 'no password' but you sometimes must hit 'enter' (without typing any characters) upon request to gain entry.
The password you are talking about would be the admin password. I believe the password he needs is a BIOS password. This password is set by admins or IT to keep the end users from altering any BIOS configurations. That password is either not set, in which case it will not ask you for it, or is set in BIOS, in which case only the person who set the password can access it.
If the password for the BIOS is forgotten there are 2 options. First, you can contact Dell and verify ownership of the system. At that time the representative will ask for the alpha-numeric code shown on the screen. This code allows the agent to generate a password that will unlock the BIOS.
Second, if ownership cannot be verified and the password cannot be remembered, the motherboard would have to be replaced. This is a security feature, hence the need for complete ownership verification.
Yes, he should be able to set the boot order using the one time boot menu (F12 at startup) without entering the BIOS password.
In the case that you are the second owner and the transfer of ownership was never submitted, the only options available are to contact the original owner, which is not always possible, or replace the board.