Video Computer System X
Video Computer System X (or Video System X, or VSX) was the original name of the 5200 prior to its release. The promotional controller was shown in Atari's marketing literature. Industrial Designer Regan Cheng spoke of the origins of the 5200's size, of Bang & Olufsen's influence on the Roy Nishi wedge, and how films like Blade Runner and 2001: A Space Odyssey influenced Atari's industrial design group (they were big fans of Syd Mead's design work in Blade Runner and elsewhere, and the matte glow of the red LED in the 5200 was inspired by HAL 9000).
Only 2 known all-black prototypes of the early version of the 5200 known as the Video System X exist. These are fully functional and all the ICs are socketed.
Only 4 known stainless steel prototypes of the 5200 known as the Video System X exist.
Note the green and red "ATARI" keys, instead of * and #.
The following photo appeared in the January 1983 issue of Electronic Games (pg 64-65):
Note how none of the buttons on the controller have any printing on them:
The same photo appeared in Consumer Guide's 1982 book How to Win at Video Games:
