[bigbuppo]

Not just a 42U rack, but a 42U rack that needs one hundred thousand watts of power, and it also needs to be able to remove one hundred thousand watts of heat out of the rack, and then it needs to dump that one hundred thousand watts of heat into space.

[JoBrad]

And it needs to communicate the data to and from a ground-based location. It’s all of the problems with satellite internet, but in your production environment!

[bigbuppo]

Based on the filing for launching a million satellites, apparently their solution is to simply launch one GPU per satellite.

[LargoLasskhyfv]

Hrrm. Lemme glassballit...

Imagine a liquid which can be electrically charged, and has a low boiling point.

(Ask 3M/DuPont/BASF/Bayer... - context 'immersion cooling')

Attach heat-pipes with that stuff to the chips as is common now, or go the direct route via substrate-embedded microfluidics, as is thought of at the moment.

Radiate the shit out of it by spraying it into the vacuum, dispersing into the finest mist with highest possible surface, funnel the frozen mist back in after some distance, by electrostatic and/or electromagnetic means. Repeat. Flow as you go.

[StephenHerlihyy]

This is sort of where I think he is going with it. Run the compute part super cold (-60C) in a dielectric fluid. Maybe even at a low pressure. It boils off, gets collected, and is then condensed into something way hotter. Like boiling water hot. This is sent through a high temperature radiator for heat dispersion (because Stefan-Boltzmann has a damned 4), and then pumped back into the common storage area. Cycle indefinitely. Beyond the simple space whatever non-sense, there is a nugget of a good idea in there. Cold things are going to have less internal resistance - so they will produce less waste heat. If you can keep them at a constant temperature via submerged cooling they are also going to suffer less thermal stress due to heat fluctuations. So the vacuum of space becomes the perfect insulator. You can’t have humans getting into them anyways because then you have to reheat and recool, causing stress on the system. Just have to accept your slow component losses. Microsoft and IBM have been working the same basic concept for a while (decade plus), Elon is just throwing ‘Space!!’ into the equation because of who he is. I think it’s 50% hype and 50% this is where the industry is going regardless. I always assumed they would just find an abandoned mine or something. But the always-cold, thermally-stable, no-humans-allowed data center is coming. We are hitting the point where the upfront cost of doing it is overshadowed by the tail cost savings.

[amluto]

> Radiate the shit out of it by spraying it into the vacuum, dispersing into the finest mist with highest possible surface, funnel the frozen mist back in after some distance, by electrostatic and/or electromagnetic means. Repeat. Flow as you go.

Even if that worked, you don’t gain much. It’s not the local surface area that matters — it’s the global surface. A device confined within a 20m radius sphere can radiate no more heat than a plain black sphere of the same radius.

There are only two ways to cheat this. First, you can run hotter. But a heat pump needs power, and you need to get that power from somewhere, and you need to dissipate that power too. But you can at least run your chips as hot as they will tolerate. Second is things like lasers or radio transmitters, but those are producing non-thermal output, which is actually worse at cooling.

At the end of the day, you have only two variables to play with: the effective radiating surface temperature and the temperature of the blackbody radiation you emit.

[bigbuppo]

hits crack pipe used by elon but only after washing it thoroughly What if we used the waste heat to power a perpetual motion device that generated electricity?