I have owned a 2600 for probly 15+ years now W/40+ games, about 2 years ago I stumbled apon a 7800 prosystem in the box W/the O.G. instructions, catalog, warrenty card the power supply, 2 joysticks, RF mod and 8 games all for 15 bucks!!!! I dont really know if the 7800 Prosystem is different than the 7800, all I know is that my old 2600 games work perfectly in it. Of th 8 games that came with, 3 of them are 7800 and the other 5 are 2600. The 3 7800 are, Centepede, Choperlifter & a better Asteroids. Of the other 5 games I scored the Ole Star Trek the motion picture game and the Empire Strikes Back(wich was the final reason I picked it all up). The system has a pause button which only works on the 7800 games. The only problem with the system it the select button sticks somtimes. Not a bad haul for a trip to Goodwill.