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Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

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Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#71

Post by pennomi »

stracer wrote: post #61
AnthonyMouse wrote: post #34

Earlier quoted context omitted.

Wait, so does this imply (ignoring the time requirements) that you could do NP calculations with a feasible amount of energy , because the inputs and outputs are small? Combine that with something that uses time dilation to make it go fast (from our frame of reference) and you'd be giving even hypothetical quantum computers a silver medal.

> time dilation to make it go fast (from our frame of reference) The only way to do that is that we move to a place from which the computer processes appear accelerated, e.g. into a strong gravity well. That isn't very useful, because we do not have such a well nearby, as only very dense hypothetical objects can provide it (e.g. black holes), and it would not be compatible with life to move there.

Doesn’t have to be compatible with life, just compatible with computing.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#72

Post by jon_richards »

XorNot wrote: post #4
wizardforhire wrote: post #2

Another notch on the belt for a cryocooler boom. Oh “superconducting is hard”, “if only we had high temperature superconductors”. All valid, but if we work with what we got and disrupt cyrocoolers make them a commodity like magnetrons all those laments become moot. Prove me wrong.

Also notable because heat rejection on that scale till you enter the superconducting regime is a reinforcing loop: the device no longer makes heat, you just need to keep the environmental heat out.

And the power requirement to maintain temperature scale by surface area, not volume. Same reason thermal power storage using giant piles of sand is theoretically viable.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#73

Post by Tuna-Fish »

pennomi wrote: post #71
stracer wrote: post #61

Earlier quoted context omitted.

> time dilation to make it go fast (from our frame of reference) The only way to do that is that we move to a place from which the computer processes appear accelerated, e.g. into a strong gravity well. That isn't very useful, because we do not have such a well nearby, as only very dense hypothetical objects can provide it (e.g. black holes), and it would not be compatible with life to move there.

Doesn’t have to be compatible with life, just compatible with computing.

You misunderstand. The problem with using time dilation is that you can only make the clock go slower, not faster. If you wanted to exploit time dilation to get a computer result faster (in subjective time), you don't send the computer to an exotic locale, you go there yourself, while you leave the computer to do work in normal space.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#74

Post by RicoElectrico »

mrguyorama wrote: post #68
actinium226 wrote: post #54

Earlier quoted context omitted.

There's something I'm missing, they say the prototype hits 2.5 GHz, how is that possible if they only have the equivalent of 5k transistors? Or is clock cycle independent of transistor count?

I'm very confused but I mean this in the utmost sincerity: What made you think transistor count and clock speed were linked? What was your line of thought? How did you think overclocking worked, by dynamically removing transistors from the chip?

GP is not entirely wrong. To achieve any reasonable speed pipelining is necessary. That is, breaking up the critical combinatorial path with registers. Which adds. transistors. Cache also is needed, which also consumes transistor budget.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#76

Post by actinium226 »

mrguyorama wrote: post #68
actinium226 wrote: post #54

Earlier quoted context omitted.

There's something I'm missing, they say the prototype hits 2.5 GHz, how is that possible if they only have the equivalent of 5k transistors? Or is clock cycle independent of transistor count?

I'm very confused but I mean this in the utmost sincerity: What made you think transistor count and clock speed were linked? What was your line of thought? How did you think overclocking worked, by dynamically removing transistors from the chip?

That's basically my question. I'm not clear on what all the transistors on a chip are doing and I'm trying to understand what the significance of a chip with only 5k transistors but able to do 2.5GHz would be. I imagine there must be some limitation, I'm just not sure what.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#77

Post by timschmidt »

actinium226 wrote: post #76
mrguyorama wrote: post #68

Earlier quoted context omitted.

I'm very confused but I mean this in the utmost sincerity: What made you think transistor count and clock speed were linked? What was your line of thought? How did you think overclocking worked, by dynamically removing transistors from the chip?

That's basically my question. I'm not clear on what all the transistors on a chip are doing and I'm trying to understand what the significance of a chip with only 5k transistors but able to do 2.5GHz would be. I imagine there must be some limitation, I'm just not sure what.

Most of the things modern microprocessors spend transistors on are clever bargains to allow the CPU to execute a single thread faster. Caches which store instructions and data closer than main memory, translation lookup buffers which store already de-referenced memory locations, pipelining which reduces the amount of work and complexity per stage so each can be clocked faster, SMT to make better use of multiple decode ports and execution units, complex additional instructions like AVX for doing more work in fewer instructions, microcode for disconnecting the underlying architecture from the instruction set allowing significantly more design freedom and implementation of legacy instructions without requiring hardware.

A design as simple as an 8 bit micro implements the instruction set directly in hardware, with minimal pipelining, no caches - just a few registers for holding values currently being worked with. They may implement a few dozens to a little over a hundred instructions vs. thousands in a modern x86. It won't have any fancy integrated peripherals like a graphics controller or NPU, just an interface to memory and a few IO pins. Even a 2.5ghz 8bit micro won't be fast compared to a similarly clocked modern x86. The micro may dispatch 1 instruction per clock or per two or four clocks, whereas the x86 might decode 6 or 8 instructions per clock per core and have as many as 20 or 30 instructions in flight at any given time per core. But the 8bit micros are just beyond a threshold of complexity which is recognizably a CPU capable of arbitrary computation upon which you can bolt on anything else you might need.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#78

Post by xenadu02 »

pennomi wrote: post #71
stracer wrote: post #61

Earlier quoted context omitted.

> time dilation to make it go fast (from our frame of reference) The only way to do that is that we move to a place from which the computer processes appear accelerated, e.g. into a strong gravity well. That isn't very useful, because we do not have such a well nearby, as only very dense hypothetical objects can provide it (e.g. black holes), and it would not be compatible with life to move there.

Doesn’t have to be compatible with life, just compatible with computing.

Time dilation means the object in the gravity well is experiencing time at a slower rate than us humans outside. That is the opposite condition we want: us slow, computer fast.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#79

Post by coryrc »

JumpCrisscross wrote: post #6
Terr_ wrote: post #3

Earlier quoted context omitted.

So someone else needs to prove a negative, that there exists no possible technology that will "disrupt" cryocoolers by bringing them to an unspecified price/performance point by an unspecified time in the future to service an unspecified computing use-case? That seems more than a little unfair. :p

> someone else needs to prove a negative, that there exists no possible technology that will "disrupt" cryocoolers Look at the Wikipedia references for crycoolers [1]. Note the dates and volume. Now look at room-tempuerature superconductors [2]. 1990 vs 2023. 5 vs 57. OP is arguing that a greater fraction of high-temperature superconducting research dollars might find purchase in improving the cryocooler than we pres…

The latter aren't being researched for CPUs, which are small things. They're for applications like long-distance power transmission, electric motors, and more. Things which aren't feasible to cryocool.

Re: Superconducting Microprocessors? Turns Out They're Ultra-Efficient (2021)

#80

Post by grahamrow »

Hugsun wrote: post #50

I'm surprised that this wasn't done earlier. An experiment like this seemed like an obvious useful thing to try the first time I heard about superconductors, some decades ago. Perhaps it is due to the technical difficulty of the experiment.

The original superconducting logic schemes were established a long time ago and companies started working on computing circuits as early as the 1960s. IBM spun out its own attempt in the early 1980s when it became apparent that this CMOS thing was going to pan out a lot faster.
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