For the full Xbox Experience, you'll need one of these

Do you own an Xbox 360 without a hard drive? Well on November 19, the new Xbox Live Experience will require you to have at least 128MB of memory available so that the update can properly install. If you find yourself in this position, you most likely purchased the since-discontinued Xbox 360 Core system.
In an effort to allow everyone who owns an Xbox 360 to enjoy the New Xbox Experience, Microsoft has announced the Xbox 360 Memory Upgrade Program. It will offer those who don't have the means to install the update two options. Customers can either enter their console's serial number on a special Web site and receive a free 512MB memory card or pay $20 for a 20GB Xbox 360 hard-disk drive.
We should note that the while the 512MB memory card will allow you to enjoy the new Xbox Live, you still won't be able to participate in Xbox Live Primetime (game shows and other entertainment) or enjoy video downloads. Because of this, we'd recommend going with the $20 offer for the 20GB hard drive. Not only is it a great deal, but you'll be able to fully enjoy everything the new Xbox Live Experience has to offer.

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