Between 1985 and 1994, Commodore produced over a dozen Amiga models spanning home computers, professional workstations, a multimedia player, and a game console. Despite the variety, they all share the same fundamental architecture: a Motorola 680x0 CPU paired with a custom chipset handling graphics, sound, and DMA.

The hardware evolved through three chipset generations:

OCS (Original Chip Set, 1985) — Agnus, Denise, Paula. The foundation: 4096-color palette, 32 on screen (or 4096 via HAM), 4-channel 8-bit audio, hardware sprites, Copper, Blitter.

ECS (Enhanced Chip Set, 1990) — Fat Agnus / Super Agnus, Super Denise, Paula. Incremental: 1 MB Chip RAM addressing, productivity display modes (e.g. 1280×200), improved sprites.

AGA (Advanced Graphics Architecture, 1992) — Alice, Lisa, Paula. Major upgrade: 24-bit palette (16.7M colors), up to 256 colors on screen (or 262,144 via HAM8), 2 MB Chip RAM, wider data paths.

The original. Announced at Lincoln Center in July 1985 with a Debbie Harry demo, the A1000 was Jay Miner's vision realized.

The A1000 was unique in having no ROM — instead, a small 8 KB bootstrap ROM at $F80000 loaded Kickstart from floppy into 256 KB of WOM (Write-Once Memory). Once written, the WOM was read-only until reset. This meant different Kickstart versions could be loaded, but it also meant a longer boot time.

The original Agnus could only address 512 KB of Chip RAM. The A1000 shipped with 256 KB and could be expanded internally to 512 KB. A "daughterboard" connector on the front panel (originally signed by the Amiga engineering team) provided the internal expansion path.

The A1000 was discontinued in 1987 when the A500 and A2000 took over.

The most successful Amiga ever made. The A500 put the Amiga into millions of homes, particularly in Europe where it dominated the home computer market alongside the Atari ST.

The A500 introduced the Fat Agnus (8375), which could address up to 1 MB of Chip RAM (though only 512 KB was fitted as standard). It also moved Kickstart into mask ROM, eliminating the A1000's floppy boot requirement.

The trapdoor expansion slot on the underside accepted a 512 KB RAM card, but this "slow RAM" sat on the Chip bus at $C00000 — accessible only by the CPU but subject to DMA contention, making it slower than true Fast RAM and inaccessible to the custom chips.

The A500 was the platform that defined the Amiga's golden age of gaming and demoscene creativity. Approximately 6 million units were sold.

The professional counterpart to the A500. Same core hardware in a big-box desktop case with internal expansion.

The A2000's defining feature was its expansion architecture. The Zorro II slots allowed true autoconfig peripherals — hard drive controllers, RAM boards, Ethernet cards, video capture devices. The dedicated CPU slot accepted accelerator boards with 68020, 68030, or even 68040 processors, transforming the machine entirely.

The video slot enabled genlocks and video production hardware, making the A2000 the standard platform for broadcast video work — famously used for weather graphics, TV titling, and the Video Toaster.

A variant, the A2500, shipped with a 68020 or 68030 accelerator pre-installed.

Commodore's most technically ambitious Amiga. A full 32-bit design that pushed the architecture forward.

The A3000 introduced Zorro III — a 32-bit expansion bus that could actually exploit the 68030's full bandwidth. It also included a built-in SCSI controller (a first for Amiga), a hardware flicker fixer (scan-doubling the 15 kHz output to 31 kHz for VGA monitors), and shipped with AmigaOS 2.0, a major OS revision.

The ECS chipset brought Super Denise, adding productivity modes like 640×480 interlaced and superhires (1280×200), and Super Agnus with full 2 MB Chip RAM addressing.

The A3000T (tower variant, 1991) offered more drive bays and expansion room. A rare A3000UX variant ran Amiga Unix (Amix), making the Amiga a certified Unix workstation.

Two transitional models that bridged OCS and AGA.

The A500+ was a minor revision — essentially an A500 with ECS and Kickstart 2.04. It was short-lived, replaced within months by the A600.

The A600 was controversial. It was smaller and cheaper than the A500 but removed the numeric keypad and the side expansion bus. Its main additions were a PCMCIA Type II slot (for memory cards and networking) and an internal IDE interface for a 2.5" hard drive. However, the lack of a CPU slot or Zorro expansion made it a dead end for upgrades.

Many in the community felt the A600 was a misstep — the resources should have gone toward getting the AGA machines to market faster.

The AGA successor to the A500 — and for many, the last great Amiga.

The A1200 was a generational leap. The AGA chipset brought:

• 24-bit color palette — 16.7 million colors available (up from 4096)
• Up to 256 colors on screen simultaneously in standard modes
• HAM8 — 262,144 colors on screen (up from HAM6's 4096)
• 2 MB Chip RAM with wider 32-bit fetch for bitplane data
• Alice replaced Agnus with improved DMA and 32-bit addressing
• Lisa replaced Denise with the expanded color capabilities

The 68EC020 was a cost-reduced 68020 — full 32-bit data and address buses but without the MMU. It ran at 14 MHz, roughly 2.5× the speed of the 68000 in the A500 for most tasks.

The trapdoor slot accepted accelerator boards with 68030, 68040, or even 68060 processors plus Fast RAM, keeping the A1200 relevant well into the late 1990s. With a Blizzard 1260 accelerator, an A1200 could outperform many contemporary PCs.

The flagship AGA desktop — Commodore's final high-end Amiga.

The A4000 combined the AGA chipset with a 68040 processor — the first Amiga with an on-chip FPU and instruction/data caches. It was a serious workstation-class machine aimed at video production and 3D rendering.

The A4000/030 variant used a 68EC030 at 25 MHz as a cost-reduced option. Both versions had Zorro III expansion for professional peripherals.

The A4000T (tower, 1994) was Commodore's last Amiga product, adding more drive bays and a more accessible internal layout. Only a small number were produced before Commodore's bankruptcy in April 1994.

Two multimedia/console variants based on existing Amiga hardware.

The CDTV was an A500 in a VCR-style case with a CD-ROM drive, positioned as a multimedia living room device. It predated the market by several years and sold poorly — consumers didn't yet understand what a multimedia player was for.

The CD32 was essentially an A1200 without a keyboard, packaged as a game console. It was the world's first 32-bit CD-ROM console, beating the 3DO and PlayStation to market. It included a custom Akiko chip that performed chunky-to-planar pixel format conversion in hardware — useful for porting PC games that used chunky pixel formats.

The CD32 sold reasonably well in Europe but was blocked from the US market by a patent lawsuit from Cad Track. Commodore's bankruptcy in April 1994 ended production.

Paula remained unchanged across all three generations. The audio subsystem — 4 channels of 8-bit DMA-driven PCM — was never upgraded in hardware, which became a growing limitation as 16-bit audio became standard on competing platforms.