[HN Gopher] IBM Demos Transistor Built for Liquid Nitrogen Cooling
       ___________________________________________________________________
        
       IBM Demos Transistor Built for Liquid Nitrogen Cooling
        
       Author : rbanffy
       Score  : 36 points
       Date   : 2024-01-07 14:35 UTC (8 hours ago)
        
 (HTM) web link (spectrum.ieee.org)
 (TXT) w3m dump (spectrum.ieee.org)
        
       | thanatos519 wrote:
       | Can I overclock it with liquid helium?
        
         | bgnn wrote:
         | Only to a limited extent. The improvements don't scale at very
         | low temperatures. Some weird stuff happens too: metals or
         | resistors can get superconducting. Not always an advantage.
        
       | cowthulhu wrote:
       | Does anyone know if there any current or near-term applications
       | for these? Seems super cost-prohibitive, especially if you can
       | just throw more compute at the problem instead. Super cool (hah)
       | either way.
        
         | jiggawatts wrote:
         | Just guessing since the article was information deficient:
         | mainframes. They're so expensive anyway that adding on a closed
         | cycle cryogenic cooler isn't even in the top ten line items on
         | the bill.
         | 
         | At cryogenic temperatures, even older architectures not
         | optimised for it can hit 9 GHz. An optimised modern CPU could
         | probably run at well over 10 GHz, which is a big performance
         | boost for legacy single-threaded code. Cooling and
         | "overclocking" the CPUs would be cheaper than rewriting the
         | code.
         | 
         | More extreme frequencies (over 100 GHz) can be achieved with
         | existing but more exotic digital electronics such as Rapid
         | Single Flux Quantum (RSFQ), which uses liquid helium cooling.
         | This is used in some military radars, radio telescopes, and a
         | few other similar high-speed signal processing scenarios. If
         | ordinary silicon could run at, say, 20 GHz with cheaper LN
         | cooling, that would lower the cost of some fancy radars.
        
           | fbdab103 wrote:
           | Liquid nitrogen costs less than a $1/liter. Not sure what
           | kind of reservoir volume they are talking, but indeed talking
           | peanuts in comparison to everything else. The salary of the
           | guy who has to maintain the cooling is going to be more.
        
         | snek_case wrote:
         | The benefit is that you can speed up any single-threaded code
         | without any changes, and not all code is easily parallelizable.
        
       ___________________________________________________________________
       (page generated 2024-01-07 23:00 UTC)