Here is the solution.  You need to edit the Autoexec.bat of the bios disk.  You will need to add the switch -forcetype to the command line that calls the bios exe.  So it should look like this PE2950_A5.exe -forcetype This will force the bios onto the chip and it will remove the McAfee bios.
We purchased 2 "still in the box" PE2950's that were built as McAfee Appliances.  While seemingly DELL in every other way, we cannot update to the current DELL BIOS (marked as CRITICAL).  We also found we cannot install a functioning OMSA application on an otherwise stable Windows 2008 x64 platform. Short of replacing the motherboards, is there a way to "FORCE" a BIOS update or otherwise return these systems to native DELL? I realize asking to hack a DELL product on an official DELL forum is less than wise but nonetheless appreciate any help / direction you can offer. Jack
Update BIOS on PE2950 McAfee Appliance