How to clear the BIOS password

I am currently trying to load a Linux operating system as a clean install on a Optiplex GX520, but can't seem to manage it because I can't reconfigure the boot order to accommodate the external CD drive attached (it doesn't have one on board). We bought a couple of these units at a business liquidation to use with our kids, and while I've been able to set up one of them without a hitch, I can't access the other one because the BIOS is password protected - and I obviously don't have a hope in hell of finding out what it is.

I was directed to the following site -http://support.dell.com/support/edoc...g/advfeat0.htm - where a solution was suggested, but try as I might I cannot find the appropriate pin that clears the password - the diagram is a little on the obscure side. I can't see a pin of any kind ANYWHERE on the board in fact.

Can anyone familiar with the board tell me how to solve the problem?

Thanks in advance...............Tim