8088-2 Processor (Intel or AMD dependent on board revision)
Onboard EGA Graphics (NSI Logic EVC315-S on early boards STMicroelectronics EGA on later revisions)
Chinon FZ-502 5.25″ 360k Floppy Drive or Epson SMD-380 3.5″ 720k Floppy Drive (Dual or Single)
Seagate ST-238R 30MB RLL Drive (Hard Disk System)
Adaptec ACB-2072 RLL Controller Card
Microsoft MS-DOS v3.21 and GW BASIC v3.2 (MS-DOS v3.3A on some later PC’s).
GEM Desktop EGA v2.2
GEM Write v1.01D
GEM Paint v2.0
Atari 83 Key XT P.C. Keyboard
Atari PCM1 Mouse
Atari PCM-124 12″ EGA Monochrome Monitor or Atari 14″ PCC 1415 EGA Monitor (later release).
Continuing the tradition of using Atari components in their PC line up, the Atari PC3 utilises the Atari STM1 Mouse (relabeled as PCM1) via an Atari mouse port conveniently located on the side of the case with the standard XT keyboard port. It also featured an Atari external floppy drive port on the rear.
Being an XT era machine, upgrades are fairly limited with just the allowance for an 8087 coprocessor to be installed in the provided socket. CPU upgrades are not possible without removing (desoldering) the 8088 processor and replacing it with a NEC V20 which will give you a slight performance increase.