Atari 800 ad from circa 1980
The Atari 400 and Atari 800 were both introduced by Atari in 1979. The biggest differences between these two machines were 1) The Atari 400 had a membrane keyboard while the 800 has a full keyboard, 2) The Atari 800 had two ROM/cartridge slots while the Atari 400 only had one, 3) The Atari 800 had more easily accessible RAM expansion and 4) The Atari 800 had additional keyboard and input/output ports. The Atari 800 at $1000 cost nearly twice as much as the Atari 400 and because of this the 400 outsold it two to one, despite the membrane keyboard.
Originally, the 400 and 800 referred to the amount of system memory each machine had. The Atari 400 was originally going to ship with 4k while the 800 would ship with 8k. Because the cost of RAM was dropping quickly at the time, both ended up shipping with 8k. It wasn’t long before the Atari 800 was shipping fully expanded with 48k of RAM.
The Atari 400/800 had very advanced graphics and sound capabilities for the time. In fact the Atari 400 was originally marketed as more of a games machine or at least a hybrid games machine/computer. Nothing really came close to these capabilities until the Commodore 64 was introduced in 1982.
Where the Atari 400/800 really had trouble was competing on price. Part of this was a timing issue. In 1979 there were very strict FCC requirements regarding signal interference that led Atari to essentially encase all of the electronics with an aluminum block. Additionally, the Atari 800 was shipping with a full complement of RAM soon after it was released and Atari’s method of RAM expansion, cartridge like modules, was expensive vs. just soldering the RAM on the motherboard. By the time the Commodore 64 was released, Commodore was able to manufacture it at a much lower cost despite being a technically similar or even slightly superior machine. Atari reacted with the XL line but was never really able to catch up. For all the problems Commodore 64 had being taken as a serious computer, Atari’s problems in that regard were much worse. Despite these problems, the Atari 8-bit line of computers was manufactured until 1992.
The above ad is for the Atari 800 from circa 1980.