Amiga 4000

The Amiga 4000, or A4000, from Commodore is the successor of the Amiga 2000 and Amiga 3000 computers. There are two models: the A4000/040 released in October 1992 with a Motorola 68040 CPU, and the A4000/030 released in April 1993 with a Motorola 68EC030. The Amiga 4000 system design was generally similar to that of the A3000, but introduced the Advanced Graphics Architecture (AGA) chipset with enhanced graphics. The SCSI system from previous Amigas was replaced by the lower-cost Parallel ATA. The original A4000 is housed in a beige horizontal desktop box with a separate keyboard. Later, Commodore released an expanded tower version called the A4000T. The machine is reported to have sold 11,300 units in Germany. The stock A4000 shipped with either a Motorola 68EC030 or 68040 CPU, 2 MB of Amiga Chip RAM and up to 16 MB of additional RAM in 32-bit SIMMs. There is a non-functional jumper that was intended to expand the "chip RAM" to 8MB. Later, third-party developers created various CPU expansion boards featuring higher-rated 68040, 68060 and PowerPC CPUs. Such hardware also typically offers faster and higher-capacity RAM (128 MB or greater). Unlike previous Amiga models, early A4000 machines have the CPU mounted in an expansion board; the motherboard does not have an integrated CPU. Later revisions of the A4000 have the CPU and 2 MB RAM surface-mounted on the motherboard in an effort to reduce costs. These machines are known as the A4000-CR (cost-reduced) and the surface-mounted CPU is a 68EC030. The cost-reduced models also make use of a non-rechargeable lithium battery for real-time clock battery backup rather than a rechargeable NiCad battery. The NiCad backup battery is one of the most common causes of problems in an aging device that uses one because it has a tendency to eventually leak. The released fluids are somewhat corrosive and can eventually damage the circuitry. The A4000 is the first Amiga model to have shipped with Commodore's third-generation Amiga chipset, the 32-bit Advanced Graphics Architecture (AGA).