Kevin_Zelhart@f24.n116.z1.fidonet.org (Kevin Zelhart) (05/01/91)
I haven't seen any serious documentation on it yet, but I imagine they have done their typical routine of cutting the bus width in half while still maintaining the main processor structure. If I see any blurbs in EE times, I'll *post them. KMZ
Alexander_Holy@f90.n310.z2.fidonet.org (Alexander Holy) (05/02/91)
> > 486SX == 486 w/o "built in" coprocessor > > 486SX == 386 ? No, no. The 486 is a complex 64-bit RISC CPU (very similar to the i860) which is microcoded to do 386 instructions. The hardware is totally different. The 486sx seems to be here for marketing reasons, now that AMD has started shipping their 386 clone CPUs. I think that the 486sx will perform like a 486 of equal speed. The question is, since it lacks the internal FPU, if there will be a 487sx. If yes, the 487sx/486sx combination is likely to perform drastically worse than a 486. If you are not interested in FPUs, the 486sx may be worth a look. Anyway, there seems to be a need for fast CPUs for doing such weird things as Windows. Clue: If Windows runs much to slow on a 286, and does not make sense to run on a 386sx with less than 2 MB, why are we still using 16bit compilers? Anyone got his hands on the new Watcom 386 C Compiler special Windows Version? ---
Johannes_Blach@p111.f11.n310.z2.fidonet.org (Johannes Blach) (05/03/91)
> If Windows runs much to slow on a 286, and does not make sense to > run on a 386sx with less than 2 MB, why are we still using 16bit > compilers? If windows runs slower in 386 mode than in Standard mode, why are wu still using Wimpdos? Servus, johi ---
Alexander_Holy@f90.n310.z2.fidonet.org (Alexander Holy) (05/03/91)
> If windows runs slower in 386 mode than in Standard mode, why are wu > still using Wimpdos? I you think twice, Windows makes no sense at all :-) Actually, a program that mostly reads a 500k file with _lread runs about 5 to 6 seconds under plain DOS, about 6 to 7 seconds under Windows in Standard Mode, and takes about 9 to 10 seconds in 386Enh Mode. The machine is a 386/20 with 8MB of RAM, so we can be sure there is no swapping. 386Enh makes sense because of simplified memory managment (no segment moving). It makes also sense to write 32-bit programs, which run significantly faster. The real problem is DOS itself. The most sensible solution would be to include DOS itself into the Windows Kernel :-( ---
Johannes_Blach@p111.f11.n310.z2.fidonet.org (Johannes Blach) (05/03/91)
> I you think twice, Windows makes no sense at all :-) You only have to think to come to this conclusion. The second though would be redundant. > The most sensible solution would be to include DOS itself into the > Windows Kernel. Please, don't even think about it. It took Mickeysoft about 10 Years to get worst bugs out of Dos. Imagine you have to start with this process again. Servus, johi ---
rafetmad@oxy.edu (David Ronald Giller) (05/06/91)
> > > 486SX == 486 w/o "built in" coprocessor > > > > 486SX == 386 ? >No, no. The 486 is a complex 64-bit RISC CPU (very similar to the i860) which >is microcoded to do 386 instructions. The hardware is totally different. What? 64-bit? RISC? Not last time I looked. The 80x86 family is about as far from the RISC concept as I can conceive. The 486 is basically just a debugged (we hope), optimized version of the 386. With a debugged (we hope) optimized version of the 387 on board. The fact that the two are in the same physical package (on the same wafer) is what gives the 486 its great floating- point power and speed. How could a processor that is coded to emulate another possibly ever execute instructions in a single cycly (as the 486 is wont to do)? The 486 is really what the 386 should have been. >The 486sx seems to be here for marketing reasons, now that AMD has started >shipping their 386 clone CPUs. I think that the 486sx will perform like a 486 >of equal speed. The question is, since it lacks the internal FPU, if there will >be a 487sx. If yes, the 487sx/486sx combination is likely to perform >drastically worse than a 486. If things at Intel haven't changed, shouldn't we expect the 486sx to be a 16- bit-bussed version of the 486? The 8086/8088 and 386/386sx have been this route. A marketing reason indeed, to be able to say 'Almost the same per- formance, at a greatly reduced price!!!'. But for I/O intensive purposes (on a 32-bit bus) this is a big mistake. Indeed, if there were a 486sx/487sx combo, I can't see its marketplace. Surely this combo will be more expensive than a 386/387, and will offer little if any performance benefit. The 386sx really lost a bit of its punch, so much so that it paled when compared to a 286 at the same speed (talking in 16-bit mode, now). >if you are not interested in FPUs, the 486sx may be worth a look. Anyway, there >seems to be a need for fast CPUs for doing such weird things as Windows. Yes, there seems to be little need for an FPU under Windows right now (unless your applications use them intensively). If, however, Windows gains display Postscript, (which, IMHO would be a positive boon, even if it is unlikely), it would arguably NEED an FPU. >Clue: If Windows runs much to slow on a 286, and does not make sense to run on >a 386sx with less than 2 MB, why are we still using 16bit compilers? Why would we want to forsake the large Windows + 286 market? Windows will, unless the horrible mistake of making it a 32-bit OS is made, continue to be the environment of choice for these very popular workhorses. Writing a 32-bit only app under Windows is really an inappropriate. Something this large (and correspondingly expensive) should be left to OS/2. And don't tell me about OS upgrade costs; this is no longer an issue. New buyers would do well to go for OS/2; it's cheaper than DOS+Windows, faster (my experiense is that it is very noticeably faster), and DEFINITELY more stable. THIS is the environment for apps that require 32-bit operation. (I don't really want to turn this into another Windows vs. OS/2 war, but the facts are there.) >Anyone got his hands on the new Watcom 386 C Compiler special Windows Version? See my above argument; however, I hear it's a good package. >--- -Dave David Giller ----- (rafetmad@oxy.edu) or (dgiller@oxy.edu) ------------ Box 134 "Some of us wake up -- others roll over." Occidental College "It's easy to deceive a child." -- John Lydon Los Angeles, CA 90041
Alexander_Holy@f90.n310.z2.fidonet.org (Alexander Holy) (05/06/91)
> Use OS/2 2.0 :-)
Sell me a package, and I'll do.
---rdthomps@vela.acs.oakland.edu (Robert D. Thompson) (05/07/91)
In article <1024862889@p111.f11.n310.z2.fidonet.org> Johannes_Blach%p111.f11.n310.z2@hippo.dfv.rwth-aachen.de (Johannes Blach) writes: > >If windows runs slower in 386 mode than in Standard mode, why are wu still >using Wimpdos? > I have found this only to be the case when running a DOS Window Session... --- Robert
daly@ecs.umass.edu (Bryon Daly, ECE dept, UMass, Amherst) (05/09/91)
In article <1024391017@f90.n310.z2.fidonet.org>, Alexander_Holy@f90.n310.z2.fidonet.org (Alexander Holy) writes: > > > 486SX == 486 w/o "built in" coprocessor > > > > 486SX == 386 ? > > No, no. The 486 is a complex 64-bit RISC CPU (very similar to the i860) which > is microcoded to do 386 instructions. The hardware is totally different. The i486 is *NOT* a 64-bit chip (Ref: i486 Hardware Ref. Manual). It is also not a RISC chip. It is fully a CISC chip, but it does have a RISC core, and have many RISC-like characteristics (pipelining, etc). I also wouldn't say the hardware is totally different. Instruction Set: same(OK, a few new instr.). Memory Addressing: same. Register Set: same. For most intents and purposes, the i486 is a 386 with faster instruction execution times, a cache built-in, and a built-in coprocessor. Take away the coprocessor, and you're basically left with a fast 386. > > The 486sx seems to be here for marketing reasons, now that AMD has started I agree with you here. > shipping their 386 clone CPUs. I think that the 486sx will perform like a 486 > of equal speed. The question is, since it lacks the internal FPU, if there will Except when doing floating point, when it will be slower than a 386 w/copro. And except that the 486SX only runs at 20MHz and the slowest 486 'DX' that intel makes is 25MHz, for a 20% loss of speed, a leap backwards in technology. > be a 487sx. If yes, the 487sx/486sx combination is likely to perform > drastically worse than a 486. Here's the joke: the 487SX is available, but performance of the combo will not suffer due to interprocessor overhead. Why? Because the 487SX *IS* a regular 486 (but at 20MHz) and it takes over all functions on the computer from the 486SX, which can then be removed. How much for this miracle of marketing technology? $200+ MORE than a regular 25MHz i486! Costs go as such: ~$250 - 486SX (20MHz) ~$550 - 486DX (25MHz), with coprocessor ~$750 - 487SX (20MHz), with coprocessor so the total 486/7SX combo is almost TWICE the cost of the 486DX, and is 20% slower! NOT cost effective at all. If you NEVER buy a copro, you save $300 big deal. The system retailer's markup will absorb most of that just because it is a "486-class" system. (Not to mention initial costs of designing new board to accomodate the the combo (they have different pin-outs, of course)). > > If you are not interested in FPUs, the 486sx may be worth a look. Anyway, there > seems to be a need for fast CPUs for doing such weird things as Windows. Don't do it! This is just a marketing scam to hurt AMD and their 40MHz 386 clone. AMD's competition spells better prices/performance for us consumers, and Intel seems to be doing all it can to avoid that. > > Clue: If Windows runs much to slow on a 286, and does not make sense to run on > a 386sx with less than 2 MB, why are we still using 16bit compilers? Good question! Doesn't Zortech C++ do 386 code, though? I hope MS & Borland decide to provide a 32 bit option soon. Perhaps in time for when Windows goes to the 32 bit flat model, sometime around Windows 7.5? :-) :-) > > Anyone got his hands on the new Watcom 386 C Compiler special Windows Version? I wish! Regards, -Bryon Daly daly@ecs.umass.edu ---- And no, I don't work for AMD, Intel, or Joe's Pizza. I'm just a concerned citizen :) looking for more bang (and less marketing BS!!!) for my buck.
dsowa@lock60.UUCP (Dave Sowa) (05/09/91)
The 486sx is a very funny chip, and is a total win for Intel in all aspects. Intel needs a chip to fend off the the fast clone 386 chips so they take the cast offs from the 486 production process, the ones where the math section fails the test process or ones that fail the tests at 25MHz and repackage them as 20MHz 486sx chips. The chips have the full 32-bit bus width so will be the same speed as a 20MHz 486 for integer operations. Should make for nice desktop windows machines. The funnier part is the 487sx chip. Intel didn't want to slow things down, so if you plug a 487sx chip into a 486sx motherboard. The 487sx takes over all processing functions from the 486sx. ie. the 487sx is really a fully functional 486 chip in a new package. This is why the 486sx chip is $258 in quantity and the 487sx is $799 in quantity. A total of $1057 for the equivalent of a slow 486 which costs $588. But as has been said many times, theres one born every minute. (The above facts are from an April 29, 1991 INFOWORLD article so if they got it wrong don't blame me. The rest is just my person opinion.) -- David Sowa Internet: dsowa@Canal.ORG UUCP: ...!uunet!cbmvax!gvlv2!lock60!dsowa
jgay@digi.lonestar.org (john gay) (05/09/91)
The 486/7sx has been pretty thoroughly discussed in comp.sys.ibm.pc.hardware, but since ya'll obviously don't read that group here is a brief (I hope) summary: 486sx is a full 486 chip with the floating point disabled. It still has the 8k cache, full 32 bit internal and external operation, but with a different pinout than the 486dx. There is a 487sx which is basically a 486dx with a different pinout then either the 486dx or 486sx. When the 487sx is installed in a machine then it becomes the main cpu and the 486sx is not used. After installing a 487sx the 486sx can be taken out of the machine (actually this is part of ibm's upgrade for their 487sx - they get the 486sx). The 486/7sx runs at 20Mhz. The combination of buying a 486sx and a 487sx is more expensive than buying a 33Mhz 486dx. Actually the list price of a 487sx is $795 - more expensive then either dx chip. General feeling on comp.sys.ibm.pc.hardware (no I don't speak for them) is just say no. It is a crippled 486dx or an expensive 386 - whichever way you want to look at it. Everyone is hoping that AMD by itself or with Cyrix (I think a good match) comes out with a 486 clone real soon now. john gay. it.
al@well.sf.ca.us (Alfred Fontes) (05/09/91)
Johannes_Blach@p111.f11.n310.z2.fidonet.org (Johannes Blach) writes: >If windows runs slower in 386 mode than in Standard mode, why are wu still >using Wimpdos? This sounds sort of like, "If virtual memory is slower than physical memory, why are you still using virtual memory?"
Curt_King@f117.n151.z1.fidonet.org (Curt King) (05/10/91)
looks like you know alot about windows :-) Im looking for a window pro. for my PC jr. any ideas?!?!? please don't tell me how retarded the jr is becuse i all redy know :-)
James_Bell@f6.n3601.z1.fidonet.org (James Bell) (05/10/91)
> Intel came up with the neat idea of being able to disable the > co-processor and sell the result as a 486sx. Yeesh! That sounds good ol' Intel to me! > In actuality, the co-processor does not lend a whole lot of speed to Yeah, I've heard that the future "487" + 486sx combo will be considerably slower than the standard 486. Have you heard what ever happened to the 386sl? I understood it was to be a low-power 386 with a cache and a true "sleep-mode". Isn't that almost exactly the same as a 486sx (but no sleep-mode) ? JB Curiouser and curiouser
poffen@sj.ate.slb.com (Russ Poffenberger) (05/10/91)
In article <165722@tiger.oxy.edu> rafetmad@oxy.edu (David Ronald Giller) writes: > >> > > 486SX == 486 w/o "built in" coprocessor >> > >> > 486SX == 386 ? > >>No, no. The 486 is a complex 64-bit RISC CPU (very similar to the i860) which >>is microcoded to do 386 instructions. The hardware is totally different. > >What? 64-bit? RISC? Not last time I looked. The 80x86 family is about as >far from the RISC concept as I can conceive. The 486 is basically just a >debugged (we hope), optimized version of the 386. With a debugged (we hope) >optimized version of the 387 on board. The fact that the two are in the same >physical package (on the same wafer) is what gives the 486 its great floating- >point power and speed. How could a processor that is coded to emulate another >possibly ever execute instructions in a single cycly (as the 486 is wont to >do)? The 486 is really what the 386 should have been. > The 486 employs many of the techniques used in RISC processors to reduce the number of clock cycles required for an instruction. This is why a 486 runs roughly twice as fast as as a 386 at the same clock. >>The 486sx seems to be here for marketing reasons, now that AMD has started >>shipping their 386 clone CPUs. I think that the 486sx will perform like a 486 >>of equal speed. The question is, since it lacks the internal FPU, if there will >>be a 487sx. If yes, the 487sx/486sx combination is likely to perform >>drastically worse than a 486. > >If things at Intel haven't changed, shouldn't we expect the 486sx to be a 16- >bit-bussed version of the 486? The 8086/8088 and 386/386sx have been this >route. A marketing reason indeed, to be able to say 'Almost the same per- >formance, at a greatly reduced price!!!'. But for I/O intensive purposes >(on a 32-bit bus) this is a big mistake. > >Indeed, if there were a 486sx/487sx combo, I can't see its marketplace. Surely >this combo will be more expensive than a 386/387, and will offer little if any >performance benefit. The 386sx really lost a bit of its punch, so much so that >it paled when compared to a 286 at the same speed (talking in 16-bit mode, now). > The 486SX was conceived due to customer pressure. Many board manufacturers wanted to "gouge" end users by offering ridiculously expensive upgrades (487SX).
timr@gssc.UUCP (Tim Roberts) (05/11/91)
Let's end the guessing about "what is the 486SX". It's been in the press. The i486SX is NOT a 16-bit version of the i486. It is, simply put, an i486 with the FPU disabled. If you buy a 486SX box, it will contain a socket for an i487. The i487 is just a full-scale i486. When you put the i487 into your 486SX box, it will disable the 486SX and take over. -- timr@gssc.gss.com Tim N Roberts, CCP Graphic Software Systems Beaverton, OR This is a very long palindrome. .emordnilap gnol yrev a si sihT
mss2696@tamsun.tamu.edu (Mark Saum) (05/11/91)
In article <1024391017@f90.n310.z2.fidonet.org> Alexander_Holy%f90.n310.z2@hippo.dfv.rwth-aachen.de (Alexander Holy) writes: > > > > 486SX == 486 w/o "built in" coprocessor > > > > 486SX == 386 ? > >No, no. The 486 is a complex 64-bit RISC CPU (very similar to the i860) which >is microcoded to do 386 instructions. The hardware is totally different. The 486 is a CISC processor. (short for Complex Instruction Set) -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Mark Saum Remote Sensing/GIS Lab Asst. Sys. Admin/Programmer Dept. of Forest Science msaum@rsgis.tamu.edu Texas A&M University -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Mark Saum Remote Sensing/GIS Lab Asst. Sys. Admin/Programmer Dept. of Forest Science msaum@rsgis.tamu.edu Texas A&M University
drift@qut.edu.au (Glenn Wallace) (05/11/91)
In article <1991May9.200635.9029@sj.ate.slb.com>, poffen@sj.ate.slb.com (Russ Poffenberger) writes: > > The 486SX was conceived due to customer pressure. Many board manufacturers > wanted to "gouge" end users by offering ridiculously expensive upgrades > (487SX). Blagards! How dare they steal a time-worn IBM technique! :-) +-------------------+-----------------------------------------+ | Glenn Wallace | Net: drift@qut.edu.au | | Drift Project | Fone: +61 7 837-7126 Fax: +61 7 221-0173| | Telecom Australia | Snail: 11th Flr 144 Edward St., | +-------------------+ Brisbane, Q4000 Australia | | | | Disclaimer - The opinions expressed must be my own, because | | Telecom is a statuatory authority and as such, | | is not capable of having opinions. | +-------------------------------------------------------------+
Johannes_Blach@p111.f11.n310.z2.fidonet.org (Johannes Blach) (05/11/91)
> Im looking for a window pro. for my PC jr. any ideas?!?!?
Sorry, I can't help you there. I have never seen this thing or known of anybody
using it. Have you tried the usual sources? Either Mickeysoft or IBM (who did
produce this contraption) should at least be able to tell if there is a working
version. If they tell you "Though luck", they may be, for once, right.
Sorry,
johi
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