Amiga 2000 - 1987 (Commodore)
A1500 , A2000 , A2000HD , A2500/020 , A2500/030, A2500UX

In 1987 Commodore released its first highly expandable machine, the A2000.
Early models are based around the A1000 design but most models are built around the A500 chip set. The A2000HD shipped with an A209x SCSI controller and a SCSI hard disk drive installed.
The A2500 has a processor card added to the A2000HD configuration.
The A1500 shipped with two floppy drives but no hard disk drive.
The A2500UX shipped with AT&T Unix System V Release 4 operating system instead of AmigaOS, a three button mouse, and usually with a tape streamer and Ethernet card.

The A1500 and A2000 have a socketed 68000 @ 7.14 MHz processor on their motherboard and they shipped with an empty processor slot. The A2500 use a processor card.
The A2500/020 shipped with an A2620 processor card featuring a 68020 and 68881 @ 14 MHz, and the A2500/030 with an A2630 featuring a 68030 and 68882 @ 25 MHz.

up to 2 MB Chip RAM,
up to 128 MB Fast RAM on processor cards,
up to 8 MB Fast RAM on Zorro II expansion cards,

Most A2000 models have 1 MB RAM soldered to their motherboard. Early models, the 3.x series, have 512 kB Chip RAM on their motherboard and 512 kB Fast RAM on their processor card.
The 4.x series have both 512 kB Chip and Fast RAM soldered to their motherboard, whilst the 6.x series have their RAM set up as 1 MB Chip RAM. Chip RAM can be expanded to 2 MB with third party expansions which replace the Agnus chip.
24 bit Fast RAM can be added using Zorro II expansion cards up to 8 MB, and 32 bit Fast RAM using processor cards featuring a 68020 or better.

Custom chips

Agnus / Fat Agnus - OCS / ECS display controller,
Denise / Super Denise - OCS / ECS display encoder,
Paula - audio and I/O controller,
Gary - system address decoder,
Buster - DMA arbitrary controller
Click for external site!