According to the official rules, you are allowed a single entry. The online entry also requires ownership of an nVidia product and, upon winning, you're required to submit a picture of you and your nVidia product. Of courser, I suppose an old graphics card, motherboard, or a borrowed card would work just fine. In that case, I'd be "buying" a friend's graphics card since I have none on hand. Hell, I've got S3 Graphics hardware but only Intel and ATI (and now I suppose AMD) products.