The original first generation of Amigas such as the A500, A600, A1000 and A2000 all used a Motorola designed 68000 CPU inside. Many Amiga users eventually upgraded theirs to have an accelerator, usually based on the 68020 or 68030 CPU. But there is a contender that is a drop-in replacement for the 68000, and for some things it can be quite a bit faster.

About the 68010

The 68010 is a minor revision to the standard 68000, it includes a few fixes, but also a few features. The majority of these are around rudimentary memory virtualisation, this is useful for users of WHDLoad in particular as it allows the key to break out of games to work properly.

On top of this was another feature called “loop mode”. This was basically a CPU cache that would work for pieces of code that ran loops with a single instruction within the loop. For example, moving blocks of memory around. These loops would be around 50% faster as a result of this.

Performance

When seen in benchmarks, this only equates to a small increase, only around 10%. But in certain games the performance increase is quite visible. Many games by the Bitmap Brothers were coded so that as much code as possible would be portable between platforms. For the 68000 CPU this meant that it had to run on Atari ST as well as Amiga. The two platforms did not have the same custom chipset, so these ended up very CPU heavy games. As such they typically benefit from a 68010 when there are a lot of sprites on the screen.

The video example below shows Xenon II running on my Commodore CDTV with both a 68000 and a 68010. In the intro you can see the 68000 starting to run a few frames behind, but when I’m playing a section of the game with lots of sprites the slowdown is very noticeable for the 68000. The game runs quite smooth throughout on the 68010, this is even more noticeable when playing the game.