Released along with the 400 in 1979, the 800 was the high-end model of the
two. The 800 is the only 8-bit Atari with a Right Cartridge slot, in addition
to the Left Cartridge slot as present on all 8-bit Ataris. Originally
released with just 8K RAM, many were sold with 16K, later on 48K was standard.
The 800 is also the only 8-bit Atari with a four-slot modular design, where
the first slot holds the CX801 (CX801-P for PAL machines) 10K ROM module, and
the other three slots hold combinations of CX852 8K or CX853 16K RAM modules.
Jason Harmon writes: (12 Feb 2004)
"..the early ones had plastic cases on the ROM and RAM modules, and had two
thumb tabs to remove the cover to access the modules. Later model 800s had
48K standard, and to improve cooling Atari installed them without the cases
but put a small plastic strip across the tops of the cards to hold them in
position. These machines also lost the thumb tabs and have regular screws to
secure the cover over the memory slots."
Only the 400 and 800 8-bit Atari models have four controller (joystick) ports.
Early 800 units include the CTIA chip; later units include the GTIA chip, also
present in all later 8-bit Ataris.
Production of the 800 ended in May 1983.