Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!dsinc!bagate!cbmvax!daveh From: daveh@cbmvax.commodore.com (Dave Haynie) Newsgroups: comp.sys.amiga.advocacy Subject: Re: The 68050 - end of the 680x0? (was Re: The Amiga's Future) Message-ID: <22365@cbmvax.commodore.com> Date: 12 Jun 91 19:15:48 GMT References: <5068@orbit.cts.com> <16647@darkstar.ucsc.edu> < <1308@cbmger.UUCP><28@ryptyde.UUCP>> <01dH!cmr@cs.psu.edu> <1991Jun10.072945.8821@neon.Stanford.EDU> Reply-To: daveh@cbmvax.commodore.com (Dave Haynie) Organization: Commodore, West Chester, PA Lines: 70 In article <1991Jun10.072945.8821@neon.Stanford.EDU> torrie@cs.stanford.edu (Evan Torrie) writes: >melling@cs.psu.edu (Michael D Mellinger) writes: >All in all, it sounds very much like the situation with the 68030 vs 68020 >- claimed "double the performance" with an evolutionary upgrade, which >actually ended up with only 25-30% improvement. If you're building full speed systems, a 68030 is _better_ than twice as fast at the same clock speed as the equivalent 68020/68851 combination. If you simply drop a 68030 into a 68020 system, the increase is more like 15%-20% (the Mac II vs. IIx|IIcx is the only pure example of this I know of; the IIci and IIfx, A2630, and all the HP 68030 systems are designed as 68030 systems). > Why do I see this as the beginning of the end? Well, by all accounts, >Intel's 80586 will be as revolutionary a chip from the 486 as the 386 >was from the 286. Who's accounts. Since the leap from 68030 to 68040 was greater than the leap from 80386 to 80486, it sure looks like Motorola's in the lead. I guess you can really pick the rumors you like until real information is released. If you keep in mind all the rumors that were around prior to the '486 and '040 introductions (the '486 "downloadable microcode, emulates any CPU at full speed" was my favorite "obviously wigged out" one). >Reports of an i860 on board, superscalar processing etc seem to dominate any >discussion of the 586. For two good reasons: [a] if you're not satisfied with a '486, you aren't likely going to be satisfied with a '586, so you like to hear about real speedups on the way, not just 2x improvement, and [b] Intel has been pushing the idea of using an i860 as a coprocessor, depite the fact it's not all that well suited to the job (thought the new one they just announced is better), simply because Intel would really, really, really, really like to get two of their expensive chips into every high end PClone, rather than just one. > If Motorola is just planning an evolutionary upgrade for the 050, I >can't see how this is going to compete head-to-head with the 586. Since you really don't know what either chip is going to do, I suggest it's far too early to start worrying about things. Also, keep in mind that Intel has much less to lose by wimping out on the '586 than Motorola does on the '050. No matter what they do, Intel will sell as many '586, '586SX (the one with the FPU disabled), '587SX, '588RC (Really Crippled), etc. as they can churn out. Motorola needs to worry about their market jumping ship to RISC processors, since the "needs to be binary-compatible" personal systems comprise much less of the Motorola market. And the 680x0 environment is a heck of a lot easier to emulate in software than the brain dead combination of MS-DOS and a '486 type CPU. > My guess is that Motorola has been told by its major 68030/040 users >that they're ready to switch away from the 680x0 family [e.g. NeXT, >Apple with possibly the 88K, HP with their own PA RISC] for their >high-end products, and so Motorola is not putting too much effort into >designing high-end follow-ups to the 68040. Considering the number of processors Motorola sells to non-desktop computer users, like VME and other industrial applications, the Apple/NeXT/Amiga use of high end 680x0s, while not trivial, is the minority. Incidently, the Enquirer, er, EE Times, rumors that Apple may be looking at IBM's "America" or whatever they call it, the processor set in the RS/6000, rather than 88K. IBM gets to port MacOS, they get a fast processor. Not that anyone, other than Apple and IBM, have a real clue at this point. -- Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests" {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: hazy BIX: hazy "This is my mistake. Let me make it good." -R.E.M.