Unlocking the BIOS setup

Yes, I'm referring to the refurbished Dell Dimension 9200 that I got working again by replacing a burnt-out video card.
OK, so now I wanted to get things up-to-date. So, I went to support.dell.com and, after adding in my Service Tag number for this computer, I was presented with a series of driver updates some of which were marked as urgent.
One of the urgent ones was in fact new BIOS firmware, so I set about a BIOS flash.
However, no go because the BIOS setup was locked and I needed to type in the administrators password.
Now, even though I was logged in (Windows Vista) as an administrator and I had also activated the Administrator user in Vista, the administrator referred to in the BIOS is NOT the same.
But what was the BIOS administrator password?
Apparently, Dell seem reluctant to provide this as somebody might actually make some BIOS changes. Yes, but what about if you need to flash the BIOS firmware?
I did an awful lot of googling but found little that was of use.
This article and another similar but a little more detailed were educational but didn't solve the problem.
I tried the Phoenix (BIOS manufacturer) backdoor passwords (PHOENIX, phoenix, BIOS, CMOS) but none worked.
I also took out the CMOS battery and left it out overnight but, once again, the password persisted.
Finally, I decided to RTFM where I found that the mobo has a jumper called CLRPASSWD which, if removed and the machine started up, removes the administrator password from the BIOS setup.
Well, in the end it was quite easy and I was then able to add an administrator password that I'm unlikely to forget (admin).
So, now I flashed the BIOS firmware and everything worked fine.