the dell disk install is looking for dell hardware. They burn information in the firmware and your install disk is looking for that. I know with server line serial is burned in as I do not activate a fresh server install....it wakes up after install all done and activated not typjng in a key.
Best you can do, windows 7/server 2008 and below as I have not done windows 8/server 2012, is get a virtual to fire up off the install disk. Activation may not work however. I do this for quick and easy testing and do not want to burn a license from our bulk corp license numbers. Basic vm....test something...and ditch it after. Guess whatever hardware vm software presents to client good enough to run for a bit. I do this with dell hardware clients as well so maybe it greases the wheels.