4 ms·

Hmm – the smallest, most highly-integrated PDP-11 (-compatible) package ever made was the QFP 1806VM2, with around ~135k transistors; it integrated MMU, UART, p

Hmm – the smallest, most highly-integrated PDP-11 (-compatible) package ever made was the QFP 1806VM2, with around ~135k transistors; it integrated MMU, UART, parallel interface, keyboard controller, etc, but did floating-point instructions in interpretive microcode. I think that same transistor count was reached by Motorola on the 68020, which would've been around 1984, but would have needed the peripheral controllers mentioned here.

WalterBright 3y ago
The FPU for the 8086 was a separate chip, and the IBM PC still required a board full of chips to make a working computer. (If I recall correctly, it wasn't until the 486 that the FPU was incorporated.)
- Aloha 3y ago
  The IBM PC had an advantage in that most of the support parts were IIRC largely jellybean 74 series logic - could a PC-PDP have used similar COTS parts? The larger issue with DEC was a strong NIH trend (almost as strong as IBM), I dont know if they could have bucked that trend to successfully launch a market winning PC. It probably would have looked like the DEC Professional, which I think looks like market failure. So the dreams of a 64 bit extension to the PDP-11 might be stillborn ;-)
  - Gibbon1 3y ago
    I read an essay by a guy that worked on project to produce a DEC minicomputer using ECL logic. And there was yet another group working on the DEC Alpha. At the time the main group was using most of the companies resources betting the company on dethroning IBM in the main frame arena. And was trying to stab the Alpha and Minicomputer group in the back. So probably not. Suspect IBM's skunk work project was done as a hedge and anti-trust reasons. Personal Computers were going to take some business away from them they wanted it to be their product not someone else. Anti-trust also meant it needed to use off the shelf stuff.
    - jacquesm 3y ago
      Between x86 and the Alpha I much preferred the Alpha. Unfortunately it was wickedly expensive and it was hard to get. But for 64 bit work it was immediately usable and rock solid. It also beat Intel/AMD by about a decade to the market and I'm still kind of surprised that DEC managed to squander that lead.
      - Gibbon1 3y ago
        I'm pretty sure if Motorola had rolled out the 68008 at the same time as the 68000 the 0x86 would be something few people remember. The hardware people choose the 8088 because it only required 8 DRAM's instead of 16.
    - varjag 3y ago
      I can't imagine Alpha and ECL based designs being done anywhere within the same decade.
      - formerly_proven 3y ago
        Alpha and VAX 9000 DEC also did a "300 MHz 125 W ECL microprocessor" in the 90s, though that seemed to be mostly about developing cooling.
      - Gibbon1 3y ago
        My memory of the 80's was most stuff was fast but power hungry NMOS. People were pushing things like GA, ECL, Silicon on Sapphire as the next thing to replace it. I might be biased but the company I worked for in the 80's switched to CMOS early[1]. I think the high end guys were ignoring CMOS despite it closing the gap relentlessly. Worse for all the other technologies as integration increased heat became a relentlessly and eventually unsolvable problem. I remember seeing ECL datasheets for simple chips that would draw a half watt. Notable volume production of CMOS grew and grew while ECL, GA didn't really. So yes, ECL for new business after 1985 was dumb. [1] CEO realized enclosures, power supplies, and fans were a large fraction of the bom.
    - TheOtherHobbes 3y ago
- xxs 3y ago
  >it wasn't until the 486 that the FPU was incorporated Indeed and 486SX had the FPU disabled. I think that was the 1st time the binning/SKUs became a marketing strategy.
Aloha 3y ago
I think DEC's strong trend line of NIH (almost as strong as IBM) almost certainly dooms a PC-PDP - IBM only made the PC by effectively creating a skunkworks within the company that was focused solely on 'go to market' compared to the normal IBM development process. I dont know if DEC could or would have done that.
- WalterBright 3y ago
  I was a DEC-head in the 70's and 80's, and along with my fellow DEC-heads anxiously awaited DEC's entry into the PC arena. Everyone was excited to see the rollout of the Rainbow, sure it would be a killer machine like other DEC machines. After the presentation, we were all in shock. It did not play to any of DEC's strengths, and was just a crummy, proprietary x86 insult. That was the end of our love affair with DEC. Very sad.
  - jacquesm 3y ago
    One of the worst own goals in the history of computing imnsho.
  - Aloha 3y ago
    IMO, part of what killed DEC was what almost killed IBM - poor management and a somewhat loathed sales force. DEC tried to go after IBM and in doing so structured itself after IBM, it lead to multiple competing projects and groups doing similar work, multiple layers of management making the company unwieldy to manage, and a sales force that had trouble building the customer relationship because of internal structures. The same thing functionally killed Motorola, and will eventually harm Cisco too (Cisco is a company that in my opinion is ripe for 'disruption').
dboreham 3y ago
68020 is much more complex than any pdp-11.
varjag 3y ago
1806VM2 wasn't released until late 1980s when there were numerous superior options, even if your yardstick is transistor count (but naturally not in USSR).
- SomeoneFromCA 3y ago
  VM1 though appeared in 1983 and arguably BK home computer was the smallest ever PDP-11
  - deleted 3y ago
    [deleted]
Someone 3y ago
> I think that same transistor count was reached by Motorola on the 68020, which would've been around 1984 Wikipedia says ~200k (https://en.wikipedia.org/wiki/Motorola_68020 https://en.wikipedia.org/wiki/Motorola_68020), so about 50% more than 135k. I don’t know much of hardware, but part of that may have been because of (https://en.wikipedia.org/wiki/Motorola_68020#020_concept_emerges https://en.wikipedia.org/wiki/Motorola_68020#020_concept_eme...): “A great debate broke out about how to refer to the underlying design of the new chip in marketing materials. Technically, the 020 was moving from the long-established NMOS logic design to a CMOS layout, which requires two transistors per gate. Common knowledge of the era suggested that CMOS cost four times as much as NMOS, and there was a significant amount of the market that believed "CMOS equals bad.”

WalterBright 3y ago

The FPU for the 8086 was a separate chip, and the IBM PC still required a board full of chips to make a working computer. (If I recall correctly, it wasn't until the 486 that the FPU was incorporated.)

Aloha 3y ago
The IBM PC had an advantage in that most of the support parts were IIRC largely jellybean 74 series logic - could a PC-PDP have used similar COTS parts? The larger issue with DEC was a strong NIH trend (almost as strong as IBM), I dont know if they could have bucked that trend to successfully launch a market winning PC. It probably would have looked like the DEC Professional, which I think looks like market failure. So the dreams of a 64 bit extension to the PDP-11 might be stillborn ;-)
- Gibbon1 3y ago
  I read an essay by a guy that worked on project to produce a DEC minicomputer using ECL logic. And there was yet another group working on the DEC Alpha. At the time the main group was using most of the companies resources betting the company on dethroning IBM in the main frame arena. And was trying to stab the Alpha and Minicomputer group in the back. So probably not. Suspect IBM's skunk work project was done as a hedge and anti-trust reasons. Personal Computers were going to take some business away from them they wanted it to be their product not someone else. Anti-trust also meant it needed to use off the shelf stuff.
  - jacquesm 3y ago
    Between x86 and the Alpha I much preferred the Alpha. Unfortunately it was wickedly expensive and it was hard to get. But for 64 bit work it was immediately usable and rock solid. It also beat Intel/AMD by about a decade to the market and I'm still kind of surprised that DEC managed to squander that lead.
    - Gibbon1 3y ago
      I'm pretty sure if Motorola had rolled out the 68008 at the same time as the 68000 the 0x86 would be something few people remember. The hardware people choose the 8088 because it only required 8 DRAM's instead of 16.
  - varjag 3y ago
    I can't imagine Alpha and ECL based designs being done anywhere within the same decade.
    - formerly_proven 3y ago
      Alpha and VAX 9000 DEC also did a "300 MHz 125 W ECL microprocessor" in the 90s, though that seemed to be mostly about developing cooling.
    - Gibbon1 3y ago
      My memory of the 80's was most stuff was fast but power hungry NMOS. People were pushing things like GA, ECL, Silicon on Sapphire as the next thing to replace it. I might be biased but the company I worked for in the 80's switched to CMOS early[1]. I think the high end guys were ignoring CMOS despite it closing the gap relentlessly. Worse for all the other technologies as integration increased heat became a relentlessly and eventually unsolvable problem. I remember seeing ECL datasheets for simple chips that would draw a half watt. Notable volume production of CMOS grew and grew while ECL, GA didn't really. So yes, ECL for new business after 1985 was dumb. [1] CEO realized enclosures, power supplies, and fans were a large fraction of the bom.
  - TheOtherHobbes 3y ago
xxs 3y ago
>it wasn't until the 486 that the FPU was incorporated Indeed and 486SX had the FPU disabled. I think that was the 1st time the binning/SKUs became a marketing strategy.

Aloha 3y ago

I think DEC's strong trend line of NIH (almost as strong as IBM) almost certainly dooms a PC-PDP - IBM only made the PC by effectively creating a skunkworks within the company that was focused solely on 'go to market' compared to the normal IBM development process. I dont know if DEC could or would have done that.

WalterBright 3y ago
I was a DEC-head in the 70's and 80's, and along with my fellow DEC-heads anxiously awaited DEC's entry into the PC arena. Everyone was excited to see the rollout of the Rainbow, sure it would be a killer machine like other DEC machines. After the presentation, we were all in shock. It did not play to any of DEC's strengths, and was just a crummy, proprietary x86 insult. That was the end of our love affair with DEC. Very sad.
- jacquesm 3y ago
  One of the worst own goals in the history of computing imnsho.
- Aloha 3y ago
  IMO, part of what killed DEC was what almost killed IBM - poor management and a somewhat loathed sales force. DEC tried to go after IBM and in doing so structured itself after IBM, it lead to multiple competing projects and groups doing similar work, multiple layers of management making the company unwieldy to manage, and a sales force that had trouble building the customer relationship because of internal structures. The same thing functionally killed Motorola, and will eventually harm Cisco too (Cisco is a company that in my opinion is ripe for 'disruption').

dboreham 3y ago

68020 is much more complex than any pdp-11.

varjag 3y ago

1806VM2 wasn't released until late 1980s when there were numerous superior options, even if your yardstick is transistor count (but naturally not in USSR).

SomeoneFromCA 3y ago
VM1 though appeared in 1983 and arguably BK home computer was the smallest ever PDP-11
- deleted 3y ago
  [deleted]

Someone 3y ago

> I think that same transistor count was reached by Motorola on the 68020, which would've been around 1984 Wikipedia says ~200k (https://en.wikipedia.org/wiki/Motorola_68020 https://en.wikipedia.org/wiki/Motorola_68020), so about 50% more than 135k. I don’t know much of hardware, but part of that may have been because of (https://en.wikipedia.org/wiki/Motorola_68020#020_concept_emerges https://en.wikipedia.org/wiki/Motorola_68020#020_concept_eme...): “A great debate broke out about how to refer to the underlying design of the new chip in marketing materials. Technically, the 020 was moving from the long-established NMOS logic design to a CMOS layout, which requires two transistors per gate. Common knowledge of the era suggested that CMOS cost four times as much as NMOS, and there was a significant amount of the market that believed "CMOS equals bad.”