Originally Posted by Charlie
Newer Archie: RiscPC & clones (RiscOS 3.6->6) Will do the above, though some older games will need patching. It's also still a 'useful' computer.
Slightly misleading (since anything above RO 3.7 is really in a different class from anything below it). I'm going to nitpick now... first off, RiscPC and above weren't "Archies" at all, since the Acorn Archimedes range ended with the A5000. The RiscPC and the (misleadingly-named) A7000 were also the last Acorn-branded machines to be produced. Although the A7000 was more or less a RiscPC clone, it didn't have DEBI slots but it did
have a floating-point calculator, but was otherwise quite similar. Later hardware diverged more; the R7500 is probably the closest to the RiscPC in that sense, while the Iyonix (XScale) and the A9Home (S3C2440) are much further diverged. I believe the Iyonix is the only RISC OS machine to have had a PCI bus and the ability to take PC graphics cards.
The latest machine, based around the Beagleboard SoC and RISC OS Open, is utterly unlike anything else. It's probably worth pointing out that RISC OS was developed by Acorn Computers Ltd (now dissolved) until the end of the 3.x line; RO4 was developed by RISCOS Ltd, while RO5 was developed by competitors Castle Technology Ltd. RO6 was developed by ROL in parallel with CTL's RO5 and isn't a true sequel, despite the version number. There's a whole lot of bloody infighting between these factions (and famous legal disputes over the code) but to cut a long story short, this is why you can't find free, legally-distributable ROM images of any RISC OS version. The links on the RPCEmuSpoon site of course point to pirate copies.
As a final note, especially for anyone wanting to pick up a cheap, second-hand Acorn from eBay: you can install RO 3.6, 3.7, 3.8 (in ROM), 4.02 (ROM or softload) and 4.39 (softload) on a RiscPC, but nothing higher. RO 3.7 is the minimum requirement for a StrongARM processor. You need an Iyonix or A9Home for RO5 or better.