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Another interesting episode "after the 486" was the switch from 32 bit to 64 bit, where Intel wanted to bury the ghost of the 8086 once and for all and switched

by rob74 7mo ago

Another interesting episode "after the 486" was the switch from 32 bit to 64 bit, where Intel wanted to bury the ghost of the 8086 once and for all and switched to a completely new architecture (https://en.wikipedia.org/wiki/IA-64 https://en.wikipedia.org/wiki/IA-64), while AMD opted to extend the x86 architecture (https://en.wikipedia.org/wiki/X86-64 https://en.wikipedia.org/wiki/X86-64). This was probably the first time that customers voted with their feet against Intel in a major way. The Itanium CPUs with the new architecture were quickly rechristened "Itanic" and Intel grudgingly had to switch to AMDs instruction set - that's the reason why the current instruction set still used by all "x86" CPUs is often referred to as AMD-64.

phire 7mo ago
What I find interesting is that Intel engineers actually designed their own 64-bit extension, somewhere along the same lines as AMD64. Intel's marketing department threw a fit, they didn't want the Pentium 4 competing with their flagship Itanium. Bob Colwell was directly ordered to remove the 64-bit functionality. Which he kind of did, kind of didn't. The functionally was still there, but fused off when Netburst shipped. If it wasn't for AMD beating them to market with AMD64, Intel would have probably eventually allowed their engineers to enable the 64-bit extension. And when it did come time to add AMD64 support to the Pentium 4 (later Prescott and Cedar Mill models) the existing 64-bit support probably made for a good starting point. Bob Colwell talks about this (and some of the x86 team vs Itanium team drama) in his quora answer and followup comments: https://www.quora.com/How-was-AMD-able-to-beat-Intel-in-delivering-the-first-x86-64-instruction-set-Was-Intel-too-distracted-by-the-Itanium-project-If-so-why-Shouldn-t-Intel-with-its-vast-resources-have-been-able-to-develop-both https://www.quora.com/How-was-AMD-able-to-beat-Intel-in-deli...
- p_l 7mo ago
  Around the time of K8 being released, I remember reading official intel roadmaps announced to normal people, and they essentially planned that for at least few more years if not more they will segment into increasingly consumer-only 32bit and IA-64 on the higher end
  - twoodfin 7mo ago
    Itanium was bonkers in lots of ways—very cool in others. But this market segmentation idea just seems absolutely insane to me in a way I’ve never had anyone satisfactorily explain. It requires Intel to voluntarily destroy the commodity economics that put their CPUs on a rocket ship to domination. It’s as if they actually bought into the RISC FUD from the 1990’s that x86 was unscalable, exactly when it was taking its biggest leaps.
    - rob74 7mo ago
      Well, TBH it wasn't all FUD - hanging on to x86 eventually (much later) came back to bite them when x86 CPUs weren't competitive for tablets and smartphones, leading to Apple developing their own ARM-based RISC CPUs (which run circles around the previous x86 CPUs) and dumping Intel altogether.
      - SonOfKyuss 7mo ago
        It is interesting how so much of the speculation in those days was about how x86 was a dead end because it couldn’t scale up, but the real issue ended up being that it didn’t scale down.
        rob74 7mo ago
        Well, it turns out that it could scale up, it just needed more power than other architectures. As long as it was only servers and desktop PCs, you only noticed it in more elaborate cooling and maybe on your power bill, and even with laptops, x86 compatibility was more important than the higher power usage for a long time. It's just when high-performance CPUs started to be put in devices with really limited power budgets that x86 started looking really bad...
    - AdamN 7mo ago
      They were trying to compete with Sun and IBM in the server space (SPARC and Power) and thought that they needed a totally pro architecture (which Itanium was). The baggage of 32-bit x86 would have just slowed it all down. However having an x86-64 would have confused customers in the middle. Think back then it was all about massive databases - that was where the big money was and x86 wasn't really setup for the top end load patterns of databases (or OLAP data lakes).
mrweasel 7mo ago
If this is true or not I don't know, but I worked on a project with an HP employee and we were talking about the Itanium. At some point the HP guy goes "You know we more or less designed that thing, right?" I would tend to believe that the Itanium is an HP product, given that they've always seems more invested in the platform than Intel.
- einr 7mo ago
  Yes, it was originally designed as a successor to HP PA-RISC and then brought to Intel. I don't know how much it changed from the original design during development at Intel.

by rob74 7mo ago

phire 7mo ago

What I find interesting is that Intel engineers actually designed their own 64-bit extension, somewhere along the same lines as AMD64. Intel's marketing department threw a fit, they didn't want the Pentium 4 competing with their flagship Itanium. Bob Colwell was directly ordered to remove the 64-bit functionality. Which he kind of did, kind of didn't. The functionally was still there, but fused off when Netburst shipped. If it wasn't for AMD beating them to market with AMD64, Intel would have probably eventually allowed their engineers to enable the 64-bit extension. And when it did come time to add AMD64 support to the Pentium 4 (later Prescott and Cedar Mill models) the existing 64-bit support probably made for a good starting point. Bob Colwell talks about this (and some of the x86 team vs Itanium team drama) in his quora answer and followup comments: https://www.quora.com/How-was-AMD-able-to-beat-Intel-in-delivering-the-first-x86-64-instruction-set-Was-Intel-too-distracted-by-the-Itanium-project-If-so-why-Shouldn-t-Intel-with-its-vast-resources-have-been-able-to-develop-both https://www.quora.com/How-was-AMD-able-to-beat-Intel-in-deli...

p_l 7mo ago
Around the time of K8 being released, I remember reading official intel roadmaps announced to normal people, and they essentially planned that for at least few more years if not more they will segment into increasingly consumer-only 32bit and IA-64 on the higher end
- twoodfin 7mo ago
  Itanium was bonkers in lots of ways—very cool in others. But this market segmentation idea just seems absolutely insane to me in a way I’ve never had anyone satisfactorily explain. It requires Intel to voluntarily destroy the commodity economics that put their CPUs on a rocket ship to domination. It’s as if they actually bought into the RISC FUD from the 1990’s that x86 was unscalable, exactly when it was taking its biggest leaps.
  - rob74 7mo ago
    Well, TBH it wasn't all FUD - hanging on to x86 eventually (much later) came back to bite them when x86 CPUs weren't competitive for tablets and smartphones, leading to Apple developing their own ARM-based RISC CPUs (which run circles around the previous x86 CPUs) and dumping Intel altogether.
    - SonOfKyuss 7mo ago
      It is interesting how so much of the speculation in those days was about how x86 was a dead end because it couldn’t scale up, but the real issue ended up being that it didn’t scale down.
      - rob74 7mo ago
        Well, it turns out that it could scale up, it just needed more power than other architectures. As long as it was only servers and desktop PCs, you only noticed it in more elaborate cooling and maybe on your power bill, and even with laptops, x86 compatibility was more important than the higher power usage for a long time. It's just when high-performance CPUs started to be put in devices with really limited power budgets that x86 started looking really bad...
  - AdamN 7mo ago
    They were trying to compete with Sun and IBM in the server space (SPARC and Power) and thought that they needed a totally pro architecture (which Itanium was). The baggage of 32-bit x86 would have just slowed it all down. However having an x86-64 would have confused customers in the middle. Think back then it was all about massive databases - that was where the big money was and x86 wasn't really setup for the top end load patterns of databases (or OLAP data lakes).

mrweasel 7mo ago

If this is true or not I don't know, but I worked on a project with an HP employee and we were talking about the Itanium. At some point the HP guy goes "You know we more or less designed that thing, right?" I would tend to believe that the Itanium is an HP product, given that they've always seems more invested in the platform than Intel.

einr 7mo ago
Yes, it was originally designed as a successor to HP PA-RISC and then brought to Intel. I don't know how much it changed from the original design during development at Intel.