Quote from winter:
This has never happened to me but I've heard of it happening a lot on FatWallet. Dell has a money back guarantee, 30 days I believe. Call Dell and tell them to you want to return it and tell them why. They lose a lot of money over a returned system (no longer new, must be sold as a refurb) so they should be willing to offer you a credit for the difference. You need to be prepared to play hardball (act like you really will return the system if they dont meet your terms)
It wasnt clear to me if you have already received it (or if they had even shipped it yet). That can make a difference. If you havent received it but its already been shipped you can refuse the shipment so you dont have to pay return shipping; If you paid for shipping then you might end up eating that but if the difference is $250 then its worth it.