First off hello all and I apologize if this has been posted before. I recently purchased Fallout3 GOTY, and I attempted to install disk 2, the DLC, but it is telling me I have to have an 360 hd connected. I have an usb hd connected that has plenty of room. FYI I have one of the new 360 slims, it only has 4 gigs internal. Question is, am I forced to purchase an internal 360 hd? ...am I not allowed to install to my usb hd?