In 1987 Atari introduced the PC-1 at the Consumer Electronics Show. This was Atari's first foray into the IBM PC Compatible market and would later be known as the Atari PC1. Priced at a US$699, it was marketed as Atari's entry level system and was soon followed by the Atari PC2 also in the same year.
The machine was an Intel 8088 PC-Clone with 512KByte RAM and onboard EGA Graphics. Uniquely it reused the Atari Megafile 44 Chassis, however this came at a cost. Unlike many other IBM Compatible XT systems on the market the slim Megafile chassis did not allow for upgrades via ISA expansion cards. Apart from being able to upgrade the RAM to 640K and to add an 8087 co-processor, you were very much limited to the original configuration of the computer.
Intel 8088 CPU
The Intel 8088 microprocessor is a variant of the Intel 8086. The 8088 has an 8-bit external bus instead of the 16-bit bus that the 8086 has. The 16-bit registers and the 1MByte address range are unchanged, however. The 8086 and the 8088 have the same execution unit (EU), only the Bus Interface Unit (BIU) differs.
The original IBM PC architecture is based on the Intel 8088. The CPU runs at 5 to 16 MHz, has a 20-bit address bus and can work together with the 8087 Co-Processor. The 8088 was launched in 1979. The 8088 is compatible with the Intel 8085.