The AmigaOne 1200 & 4000 are 6xPCI + 1xAGP stand-alone G3/G4 boards capable of running the Amiga DE directly. These boards are designed to fit in Z4-busboard-compatible A1200 towers and Eyetech/Elbox/Power A4000 towers. However both AmigaOne boards can optionally connect to the appropriate Amiga motherboard for access to Classic Amiga chipset hardware. In this mode - because it has access to all the Classic Amiga custom chips - the AmigaOne 1200/4000 can also be used to run the Classic Amiga OS & software with a very high degree of compatibility.

It is important to note that the A1200/A4000 'computer' now resides on the AmigaOne board - having direct high-speed access to all the AmigaOne's PCI/AGP peripherals, and only accessing the existing A1200/A4000 chipset (via the A1200 edge connector or the A4000 CPU connector) as and when required. Any existing 680x0 or PPC accelerator is entirely redundant, its function being carried out by the AmigaOne's G3/G4 CPU & memory. For this reason a pass-through accelerator slot on either the A1200 or A4000 version of the AmigaOne is completely pointless and therefore not included.

As well as fitting into a Z4-compatible tower, the AmigaOne 1200 will also fit into a standard ATX tower case using an optional fitting kit. This makes an ideal solution for applications / operating systems that do not require the original AA chipset to be present.