The basic warranty is one year, return to depot. It starts on the ship date when you buy direct from Dell.
For systems shipped to retailers, the warranty starts on shipment, and is re-set when you register the system with Dell. However, though there's a grace period of a few months, it sounds like your system has been sitting on a shelf with that retailer for almost a year -- possibly longer. In these cases, Dell won't extend a full year warranty to you.
Since you purchased a "new old stock" system, I'd make sure you either received a substantial discount on the system (much as buying a "last year" model car), or that you negotiate some other discount (such as an extended warranty) with the seller -- or, if they won't, return the system for a refund and buy a newer system. After all, you're doing them a favor by buying a system that was otherwise costing them money to keep on the shelf.
