MC68EC060RC50 vs. MC68040RC25

[Bandaren]

I'm wondering about how a MC68EC060 would perform in a amiga.

What would happen with programs that requires a FPU? Would a 68040 with a FPU beat the 68060 here?.

Is it possible to emulate the 68040 FPU with a 68EC060?

Please bring on your ideas and thoughts! Perhaps someone have numbers and benchmarks? :-P

regards
Dan Andersson

[mikeymike]

I don't know that much about the differences in architecture between the 040 and 060EC, however, regarding your question "which would run programs faster", it depends entirely on what sort of programs you were intending to run, and that involves knowing whether some programs tax integer-crunching capabilities or floating point math functions more.

Generally I think that an FPU is needed for many functions that average users ask of their hardware, so initially I'd be more inclined to go for the 040FPU from that point of view.

However, the 060 is generally acknowledged to be very much better than the 040.  Without an FPU though, I can't say.  Two definite differences are that the 060 is generally clocked 10 or 20MHz higher than the 040, and also it doesn't require a heatsink/fan, whereas the 040 does (not a very big one, but still).

[Bandaren]

Well my primary concern would be what programs I actually could use with a 68EC060.

When you look at various programs enhanced for 68060 one would expect they are made to take advantage of the FPU.

So what would that leave me? I would have to use 68000/68020/68030 without FPU versions? In this camparison I see no reason to "upgrade" from a 68040 with FPU, it would be a downgrade.

I know there are Apollo 1260's out there with 68EC060 75Mhz how do they solve this problem?

regards
Dan Andersson

[mikeymike]

Most applications have a 040 optimised version as well.

[Karlos]

The FPU of the full 68060 is one of the principal reasons to get it. It can do a multiply in just 2 cycles IIRC.

Stuff heavily optimised for 060 tends to use the FPU for some operations that would be integer on other 68K processors, simply because it is so much quicker (especially multiply/divide)

If you want a 75MHz 060, overclock a genuine (ie labelled) 66MHz part (with a good heatsink/fan).

If speed is your primary concern, getting an 060 without the FPU is pointless IMHO.

Cards without the FPU have to either rely on some form of emulation or simply won't run stuff that requires an FPU (I think the former is more likely).
But the emulation is likely to suck in speed terms. Couple this with code that thinks there is an FPU and was written to use it for speed and the EC060 looks less and less favourable.

[PMC]

As far as my experience with an EC060 goes there's no noticeable difference in speed against a full featured 040.

I bought an '060 from a UK Amiga hardware dealer a while back (no clues given, other than the name contains the word ANAL) which instead of the fully loaded '060 I ordered turned out to be equipped with a 66Mhz EC version.  As a result, all my FPU/MMU preferred programs fell over, and the only thing that did work was Frontier.  This was played at an identical framerate to my 40Mhz 040 - but in fairness, this is probably due to the lack of 060 specific support in a game coded way back in 1993, long before the 68060 actually appeared.

Moral of the story - MHz isn't everything!

[Corrie]

I agree, you should have a look at a full 68060 @ 50Mhz and consider overclocking it to 66Mhz. That way you have the extra speed and you have the full FPU/MMU aswell!

[Ilwrath]

Yeah, the full 060 is best, by far.  Still, if given the choice between a 040 and an EC060, I'd take the EC060. Lower power requirements, less heat, newer chip.  My A4000 desktop w/ 040@25 ran HOT, to say the least.  The upgrade to 060@50 actually cooled the machine, somewhat.

[Karlos]

Ilwrath wrote:
Yeah, the full 060 is best, by far.  Still, if given the choice between a 040 and an EC060, I'd take the EC060. Lower power requirements, less heat, newer chip.  My A4000 desktop w/ 040@25 ran HOT, to say the least.  The upgrade to 060@50 actually cooled the machine, somewhat.

If the choice were between EC040 and EC060 I'd agree. But No way would I sacrifice the MMU/FPU. Too much stuff uses it these days.
I'd guess even with suitable software emulation, the EC060 would have lower floating point performance than an 040 25MHz.

You just can't run many 060 optimised programs without the FPU.