When you removed the CMOS battery how long did you keep it out? Unless you have access to the MoBo itself and could hold the switch down, you probably didn't give enough time for the capacitors to...

Many DELL versions of BIOS have a "backdoor" password to bypass this in MFG or troubleshooting environments. This backdoor password is Dell (or DELL).

Give those a shot.

Don't recognize the Model number... is this an Intellistation or a rack server? I'm fairly confident it isn't a blade.... However you should be able to hit F1 to go into BIOS settings and find the...

Is there a speed mismatch? Any POST errors or entries in the System Event Log ? Does it just give a blank screen or does it *try* to boot but falls through all startup options?