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New superconductor microprocessor yields a substantial boost in efficiency

spectrum.ieee.org

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Re: New superconductor microprocessor yields a substantial boost in efficiency

#91

Post by jcims »

Enginerrrd wrote: post #80
freeqaz wrote: post #32

Earlier quoted context omitted.

Mind expanding on this a bit more? What is that that limit and how does it relate to the clock speed?

It's not about clock speed per se. It's about the lowest possible energy expenditure to erase one bit of information (or irreversibly destroy it by performing a logical operation). The principle comes about from reasoning about entropy loss in said situations. There's a hypothesized fundamental connection between information and entropy manifest in physical law. The idea is that if you destroy one possible state of a…

Is there an idea of entropic potential energy/gradient/pressure? Could you differentiate encrypted data from noise by testing how much energy it requires to flip a bit?

Re: New superconductor microprocessor yields a substantial boost in efficiency

#92

Post by inglor_cz »

reasonabl_human wrote: post #83
inglor_cz wrote: post #55

Nice, but requires 10 K temperature - not very practical. Once this can be done at the temperature of liquid nitrogen, that will be a true revolution. The difference in cost of producing liquid nitrogen and liquid helium is enormous. Alternatively, such servers could be theoretically stored in the permanently shaded craters of the lunar South Pole, but at the cost of massive ping.

I wouldn’t want to be on call when something breaks on the moon.... Astronaut DRIs?

"Oh no, we bricked a lunar computer! Go grab your pressure suit, Mike! Back in a week, darling... Tell your mother I won't be attending her birthday party."

Re: New superconductor microprocessor yields a substantial boost in efficiency

#93

Post by tedsanders »

juancampa wrote: post #84
inglor_cz wrote: post #55

Nice, but requires 10 K temperature - not very practical. Once this can be done at the temperature of liquid nitrogen, that will be a true revolution. The difference in cost of producing liquid nitrogen and liquid helium is enormous. Alternatively, such servers could be theoretically stored in the permanently shaded craters of the lunar South Pole, but at the cost of massive ping.

> The difference in cost of producing liquid nitrogen and liquid helium is enormous. Quick google search yields: $3.50 for 1L of He vs $0.30 for 1L of H2. So roughly 10 times more expensive.

That price is more than a decade out of date. Helium has been about 10x that the past half decade. I used to pay about $3,000 per 100L dewar a few years ago. Sounds like that price was still common in 2020: https://physicstoday.scitation.org/do/10.1063/PT.6.2.2020060...

Plus, liquid helium is produced as a byproduct of some natural gas extraction. If you needed volumes beyond that production, which seems likely if you wanted to switch the world's data centers to it, you'd be stuck condensing it from the atmosphere, which is far more expensive than collecting it from natural gas. I haven't done the math. I'm curious if someone else has.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#94

Post by andrelaszlo »

Not a physicist so I'm probably getting different concepts mixed up, but maybe someone could explain:

> in principle, energy is not gained or lost from the system during the computing process

Landauer's principle (from Wikipedia):

> any logically irreversible manipulation of information, such as the erasure of a bit or the merging of two computation paths, must be accompanied by a corresponding entropy increase in non-information-bearing degrees of freedom of the information-processing apparatus or its environment

Where is this information going, inside of the processor, if it's not turned into heat?

Re: New superconductor microprocessor yields a substantial boost in efficiency

#95

Post by akiselev »

undersuit wrote: post #23
jcfrei wrote: post #13

Does superconductivity remove or reduce the limit on die size?

I'm making a naive guess here. No, superconducting transistors are probably harder to create than non super conducting transistors so the limits on die size from defects are even more pronounced and superconducting doesn't change the speed of light for electrons on the chip so it doesn't change the timing issues arising from large dies.

The limits on die size for the competitive consumer chip market are nothing like that of the B2B market. Largest chip ever made was over 40,000 mm^2 [1] compared to Intel's 10900K at ~205 mm^2. In production mainframe chips like IBM's Z15s are on the order of 700mm^2. The fab process has a lot of levers so very low defect rates are possible but not at the scale of a consumer CPU.

[1] https://techcrunch.com/2019/08/19/the-five-technical-challen...

Edit: I assume a supercoducting microprocessor would use a strategy similar to the AI monolith in [1]. Just fuse off and route around errors on a contiguous wafer and distribute the computation to exploit the dark zones for heat dissipation.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#96

Post by titanomachy »

jetrink wrote: post #57
benibela wrote: post #54

Earlier quoted context omitted.

In Sundiver by David Brin they put all the heat in a laser, so they can beam it away from their craft

Is it possible to do this without violating the second law of thermodynamics?

Definitely possible to put some of the heat into a laser. It's simple to turn a temperature gradient into an electrical potential [0], and if you use that electricity to power a laser it will convert away some of the hat.

[0] https://en.wikipedia.org/wiki/Thermocouple

Re: New superconductor microprocessor yields a substantial boost in efficiency

#97

Post by aqme28 »

andrelaszlo wrote: post #94

Not a physicist so I'm probably getting different concepts mixed up, but maybe someone could explain: > in principle, energy is not gained or lost from the system during the computing process Landauer's principle (from Wikipedia): > any logically irreversible manipulation of information, such as the erasure of a bit or the merging of two computation paths, must be accompanied by a corresponding entropy increase in no…

I was curious about this too. This chip is using adiabatic computing, which means your computations are reversible and therefore don't necessarily generate heat.

I'm having trouble interpreting what exactly that means though.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#98

Post by ladberg »

andrelaszlo wrote: post #94

Not a physicist so I'm probably getting different concepts mixed up, but maybe someone could explain: > in principle, energy is not gained or lost from the system during the computing process Landauer's principle (from Wikipedia): > any logically irreversible manipulation of information, such as the erasure of a bit or the merging of two computation paths, must be accompanied by a corresponding entropy increase in no…

It's still getting turned into heat, just much less of it. The theoretical entropy increase required to run a computer is WAY less than current computers (and probably even the one in the article) generate so there is a lot of room to improve.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#99

Post by ryukafalz »

avmich wrote: post #69
carlmr wrote: post #56

Earlier quoted context omitted.

>Not that that's necessarily a bad thing, if we're getting more than proportionally more utility out of the processors The trend seems to be that we get only a little bit of extra utility out of a lot of extra hardware performance. When the developer upgrades their PC it's easier for them to not notice performance issues. This creates the situation where every few years you need to buy a new PC to do the things you a…

I'm sure a lot of developers upgrade their PCs (they were called workstations at a time) because of material problems - keyboards getting mechanically worse, and laptops can't easily get keyboard fixed, screens getting dead pixels, sockets getting loose, hard-to-find batteries getting less charge, and maybe some electronics degradation. Another reason is upgrades to software, which maintain general bloat, and which i…

>laptops can't easily get keyboard fixed

This is a frustrating part of recent laptops, but it doesn't have to be this way - my X230's keyboard is removable with a few screws.

Re: New superconductor microprocessor yields a substantial boost in efficiency

#100

Post by Jweb_Guru »

hacknat wrote: post #36
b0rsuk wrote: post #10

Given the cooling requirements, I suppose it would create completely impassable rift between datacenter computing and other kinds. Imagine how programming and operating systems might look in a world where processing power is 80x cheaper. Considering that "data centers alone consume 2% of world's enegy", I think it's worth it.

> Imagine how programming and operating systems might look in a world where processing power is 80x cheaper. Just wait 10 years?

Not sure if you noticed, but Moore's Law died quite awhile ago now.
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