Hey,
I am just curious...can someone make an Amiga FPGA 060 that can run at 233 Mhz? Is it possible? How expensive would it be to make it?
Firstly, it's not about creating an FPGA 68060, it's about creating a compatible implementation of the 68060 ISA (IIRC the 68020 ISA is a better target in terms of instructions to implement) that can achieve an overall higher performance, be that via higher IPC (instructions per clock) or higher clocks, or both.
For example, the FPGA core in the Vampire 600 board has a lower IPC than a vanilla 68000, but it runs a lot faster, so the overall speed is improved.
Anyway, with today's FPGA technology, it should be getting to a point where once someone designs a 68020 compatible core that clocks high enough and has decent IPC, we could be looking at higher overall performance than a classic 68060. But it won't be cheap, but OTOH you won't need to worry about specific uncommon revisions of the 68060.