Need a Commodore motherboard? Believe it or not you’re in luck

Individual Computers is working on, of all things, a replacement Amiga motherboard that will fit in an Amiga 500 or Amiga 1200 case.

The board will use the AGA chipset that the Amiga 1200 used, but the board will be built using a modern process, modern materials, and as many other modern components as possible.

The same company took the same approach to a replacement Commodore 64 motherboard last year. By all accounts the board worked well. The 64 has the same problem as the Amiga–its key chips haven’t been produced in nearly a quarter century, so it had empty sockets for the most expensive chips so you could supply your own if you had them, the easier chips were supplied, and if modern replacements were available for anything without changing the behavior of the machine, Individual Computers used those. The result was a reliable, highly compatible board–no patents to worry about infringing at this late date–that uses far less power than an original due to a lower component count. And most critically, it used a modern power supply. Most C-64 problems long ago were due to the incredibly dodgy original power supplies that would blow random chips on the motherboard as they died. A C-64 Reloaded with a decent modern power supply could likely survive decades of heavy use.

The link above has all the important details, but they’ve modified the design so it will work with standard PC floppy drives, which are cheap and plentiful while Amiga drives are anything but. Another consideration is they didn’t include a CPU on the board. To a non-Amigan this probably sounds very strange, but third-party accelerator boards were extremely common on the Amiga. Rather than sell someone a CPU they probably won’t use, they just put a CPU slot on it, so someone who wants something close to a stock Amiga 1200 can plug a 68020 card in, while someone who wants a hotrod can plug in a 68060 or PowerPC board. Or anything in between.

The other odd concept to non-Amigans is the concept of chip and fast RAM. Rather than putting memory on a video card, like PCs do, Amigas had two banks of memory. One bank was available to the CPU and to the sound and video chips, so the video chip always had the memory it needed, but the CPU could dip into that memory if it needed it. Back when 512 MB of RAM was crazy expensive, that was a critical feature. The other bank of memory was available only to the CPU. Access was faster since the CPU didn’t have to share the bandwidth, so they called that fast RAM. Modern memory is so much faster than vintage memory that Individual Computers can make chip RAM run just as fast as fast RAM, so an Amiga Reloaded will always outrun a vintage Amiga if only because of the faster chip RAM. I remember a company called Black Knight Peripherals advertised a product that sped up chip RAM, but I don’t know how it worked or if it ever came to market.

The Amiga Reloaded uses a modern laptop power supply. Amiga power supplies weren’t nearly as bad as 64 power supplies were, but they aren’t common anymore, so using a cheap, common modern replacement is something everyone will appreciate.

And of course the board is designed to use flash memory, like the Amiga 1200 and 600 were able to do. This is of course far faster than a hard drive, particularly a vintage hard drive, and incredibly cost effective today. It won’t keep pace with a modern SSD, but that’s fine–Amiga OS is smaller than most of today’s security patches are, so gigabytes-per-second transfer rates would be largely wasted anyway.

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