OVERTALK
There should be no difference between the keyboards (unless as ORAC suggests it is a USB version)
However I have found in the past that it is not always the delete key that provides access to the BIOS.
Have you tried:
F1
F2
F10
SPACE
DEL
I have been octopus like hitting just about every key trying to gain access.
Apart from those borrow a keyboard and try your usual.
Good luck.