M17xR4 Power Supply Issue

From the response of Dell's support people, this apparently is not rare, as the first guy I talked to pretty much immediately said I might need a mainboard replacement.

My Alienware gives a message that sounds roughly like this:

"Please plug in an original Alienware power supply, or performance will be reduced"

Of course, I do have my original and fairly new Alienware Powersupply plugged in, but the M17x fails to recognize it.

If anyone here has any experience with that, I'd like to know if there's some simpler fix than some Dell tech coming by and doing open heart surgery on my unit.