Million Instructions per Second

[psxphill]

Lots of 6502 instructions are executed in just 2 clock cycles, so the .5 MIPS estimate is correct.

It's .5 MIPS maximum though, on the c64 you don't get to access ram often enough to meet that unless you turn off the display & not all instructions fit in 2 clock cycles.
 
Using those same conditions the 68000 in the Amiga should be able to reach 3.5 MIPS.
 

Yeah, the 8088 was a pretty badly-hobbled design - like the original 68000 it had a data bus half the width of its registers, and on top of that it didn't have nearly as many registers and they all had special-purpose functions, so a lot of time had to be wasted juggling them in any halfway complex code. And that's not even getting into a lot of the performance-inhibiting cost-saving measures like memory wait states that many PC manufacturers employed...

Comparing an 8088 to a 68000 is a little unfair. It was just the cost reduced version of the 8086, like the 68008 was a cost reduced version of 68000. Yes the 8086 wasn't a great design, but they didn't expect it to define the industry. It was just a logical progression from the 8008 chip that they produced in 1972 & they started making CPU's to give people a reason to buy the RAM chips they made to put them in calculators etc. The Intel iAPX 432 was their 68000 equivalent, but the project failed miserably. Quite often it's the cheap project that is thrown together that is successful (which is why we ended up with VHS over Betamax or any of the others). The 80386 was the first good CPU they made in the x86 line, still crippled a little by the 8086 instruction set but it had an MMU. The tried again to replace x86 with the Intel I860 but that was a commercial failure. It wasn't good enough to throw away backward compatibility, but it was great at doing specific things so it ended up on graphics accelerator cards. They were trying to do something revolutionary with that and unfortunately that group wasn't focused on what the industry needed.
 
However the 8088 does compare well to a 6502. The c64 beat CGA PC's in terms of games because of the vic & sid chips.

[psxphill]

Yes and no. The 8088 is definitely more powerful from an architectural standpoint, and faster, fundamentally, at 16-bit operations. On the other hand, the bottleneck imposed by the 8-bit bus is seriously crippling for it, and it's not as cycle-efficient to begin with

It is only a problem when you're doing 16 bit loads and stores, which you'd have to do with two separate accesses on the 6502 as well. I haven't done a comparison of every instruction but the fastest 8088 instruction is supposed to be 2 clock cycles.
 
If running on the same ram then they are probably around the same speed cpu wise, but with support for more ram in the 8088 and 16 bit maths when you need it.
 
I like the 6502 & it's main feature was the low cost, so not having some of the more expensive stuff is fine.
 
The 68000 was ubber expensive though, so it's unsurprising that it has more features.