5 ms·

How so? SX was always the crappy version.

wruza 5y ago
I was also confused by this statement and had to refresh my memories. In short, 386sx had 16/24 bus instead of 32, which made it 286 main board compatible. 486sx was simply non-fpu version.
- pjmlp 5y ago
  As 386SX owner, it was also the no-FPU version.
  - donio 5y ago
    None of the 386 models had on-chip FPU. That came with the 486.
    - kazinator 5y ago
      Moreover, there was an 80387SX copro to go with the 386SX.
      - jacquesm 5y ago
        And, for us oldies the Weitek as well as the DSP32 board. https://en.wikipedia.org/wiki/Weitek https://en.wikipedia.org/wiki/Weitek and https://www.signalogic.com/images/Ariel_DSP32-PC.jpg https://www.signalogic.com/images/Ariel_DSP32-PC.jpg
        kjs3 5y ago
        And if you're old and a bit odd, there were i486+i860[1] motherboards from (at least) Hauppauge, Microway & Olivetti. [1] https://old.hotchips.org/wp-content/uploads/hc_archives/hc02/3_Tue/HC2.S6/HC2.6.4.pdf https://old.hotchips.org/wp-content/uploads/hc_archives/hc02...
        jacquesm 5y ago
        I never got my hands on one of those. But I did get to play with Transputers, which was another interesting co-processor option.
        kjs3 5y ago
        Transputers are still a thing from ST Micro, I think, though targeting the embedded market now. I got to use a Meiko 'Surface' transputer supercomputer back in the day. Interesting toy. The i486+i860 combo I played with ended up being not particularly interesting. By the time it showed up, Pentium was eminent so the i486 was old news and the i860 was a huge pain in the ass to get anything like promised performance out of.
        jacquesm 5y ago
        Meiko, there's another name that I haven't heard for a really long time. Are there any Transputer based systems still in use?
        kjs3 5y ago
        Yeah...the Meiko was pretty nifty, and Occam was an interesting language. Like I said, ST Micro picked up the Transputer line via acquisition. They morphed it into more of an embedded product, and targeted things like set-top boxed. Pretty sure it was the ST20 line. Unfortunately, a very quick look at the web site makes it look like ST did what everyone else in the embedded world seems to be devolving to: everything is an ARM. So...there are probably descendants of Transputer still chugging along out there, but doesn't look like it has a future.
        balls187 5y ago
        I remember learning "Hauppauge" was pronounced "Hop Hog"
  - anyfoo 5y ago
    That's the point. With the 386, it means bus width, the FPU was separate as the 387 anyway. With the 486, it meant whether it had an FPU. I'm not getting into the whole controversial deal with whether the 486SX actually just had the FPU disabled, and what the 487 actually was, because there seems to be a lot of misconception around that that I don't want to inadvertently repeat: http://www.os2museum.com/wp/lies-damn-lies-and-wikipedia/ http://www.os2museum.com/wp/lies-damn-lies-and-wikipedia/
gruturo 5y ago
True, but SX used to stand (officially? dunno) for Singleword Xchange, as it had a 16 bit bus. DX was Doubleword Xchange, hence 32bit bus. Then in the 486, the bus was always 32-bit (at least from Intel. I have a faint memory of Cyrix 486SLCs with a 16bit bus), and now the SX-DX indicated the presence of an integrated FPU instead. Bonus: the 80487 was not just an FPU. It was a full 486DX which just disabled the main CPU and did all the work, and of course had an FPU.
- guerrilla 5y ago
  > Singleword Xchange > Doubleword Xchange Thank you! I knew all the difference (the same as 8088 vs. 8086) but never knew why those names were used. I love these tidbits of history.
balls187 5y ago
Others have mostly answered it. As a 486DX owner (IBM PC compatible AST Advantage), I was aware of the lower price point 486SX chip, and the difference was that the latter did not have hardware support for floating point calculations. In marketing jargon, the 486DX had an "integrated math co-processor." I was also aware of the previous generation also using DX/SX designations, and until recently, assumed that the SX designation also meant a lack of a math co-processor, when instead, it simply meant a 16-bit data bus, compared to the 32bit data bus of the DX chip, and that neither DX or SX variant of the 386 had dedicated hardware for floating point calculations.

I was also confused by this statement and had to refresh my memories. In short, 386sx had 16/24 bus instead of 32, which made it 286 main board compatible. 486sx was simply non-fpu version.

pjmlp 5y ago
As 386SX owner, it was also the no-FPU version.
- donio 5y ago
  None of the 386 models had on-chip FPU. That came with the 486.
  - kazinator 5y ago
    Moreover, there was an 80387SX copro to go with the 386SX.
    - jacquesm 5y ago
      And, for us oldies the Weitek as well as the DSP32 board. https://en.wikipedia.org/wiki/Weitek https://en.wikipedia.org/wiki/Weitek and https://www.signalogic.com/images/Ariel_DSP32-PC.jpg https://www.signalogic.com/images/Ariel_DSP32-PC.jpg
      - kjs3 5y ago
        And if you're old and a bit odd, there were i486+i860[1] motherboards from (at least) Hauppauge, Microway & Olivetti. [1] https://old.hotchips.org/wp-content/uploads/hc_archives/hc02/3_Tue/HC2.S6/HC2.6.4.pdf https://old.hotchips.org/wp-content/uploads/hc_archives/hc02...
        jacquesm 5y ago
        I never got my hands on one of those. But I did get to play with Transputers, which was another interesting co-processor option.
        kjs3 5y ago
        Transputers are still a thing from ST Micro, I think, though targeting the embedded market now. I got to use a Meiko 'Surface' transputer supercomputer back in the day. Interesting toy. The i486+i860 combo I played with ended up being not particularly interesting. By the time it showed up, Pentium was eminent so the i486 was old news and the i860 was a huge pain in the ass to get anything like promised performance out of.
        jacquesm 5y ago
        Meiko, there's another name that I haven't heard for a really long time. Are there any Transputer based systems still in use?
        kjs3 5y ago
        Yeah...the Meiko was pretty nifty, and Occam was an interesting language. Like I said, ST Micro picked up the Transputer line via acquisition. They morphed it into more of an embedded product, and targeted things like set-top boxed. Pretty sure it was the ST20 line. Unfortunately, a very quick look at the web site makes it look like ST did what everyone else in the embedded world seems to be devolving to: everything is an ARM. So...there are probably descendants of Transputer still chugging along out there, but doesn't look like it has a future.
        balls187 5y ago
        I remember learning "Hauppauge" was pronounced "Hop Hog"
- anyfoo 5y ago
  That's the point. With the 386, it means bus width, the FPU was separate as the 387 anyway. With the 486, it meant whether it had an FPU. I'm not getting into the whole controversial deal with whether the 486SX actually just had the FPU disabled, and what the 487 actually was, because there seems to be a lot of misconception around that that I don't want to inadvertently repeat: http://www.os2museum.com/wp/lies-damn-lies-and-wikipedia/ http://www.os2museum.com/wp/lies-damn-lies-and-wikipedia/

gruturo 5y ago

True, but SX used to stand (officially? dunno) for Singleword Xchange, as it had a 16 bit bus. DX was Doubleword Xchange, hence 32bit bus. Then in the 486, the bus was always 32-bit (at least from Intel. I have a faint memory of Cyrix 486SLCs with a 16bit bus), and now the SX-DX indicated the presence of an integrated FPU instead. Bonus: the 80487 was not just an FPU. It was a full 486DX which just disabled the main CPU and did all the work, and of course had an FPU.

guerrilla 5y ago
> Singleword Xchange > Doubleword Xchange Thank you! I knew all the difference (the same as 8088 vs. 8086) but never knew why those names were used. I love these tidbits of history.

balls187 5y ago

Others have mostly answered it. As a 486DX owner (IBM PC compatible AST Advantage), I was aware of the lower price point 486SX chip, and the difference was that the latter did not have hardware support for floating point calculations. In marketing jargon, the 486DX had an "integrated math co-processor." I was also aware of the previous generation also using DX/SX designations, and until recently, assumed that the SX designation also meant a lack of a math co-processor, when instead, it simply meant a 16-bit data bus, compared to the 32bit data bus of the DX chip, and that neither DX or SX variant of the 386 had dedicated hardware for floating point calculations.