alt Hacker NewsTo remove heat by radiation there's a big benefit to running the GPUs hotter as the radiation will be proportional to the fourth power of temperature. This resource is using 85 deg C versus 60 deg C for OP which will improve cooling performance.
If Nvidia/SpaceX can make the chips run at a higher temperature that would help a lot although I assume it would have already been done if it were possible. Another option is to add a heat pump to raise radiator temperature if the smaller radiator mass can pay for the heat pump mass.
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Could they run the chips at "normal" temperatures and then heat pump that all into some other mass that lives at "aerospace alloy" temperatures and radiates it away more efficiently?
Sorry but wouldn’t space based DCs need radiation hardened parts which are typically a few generations behind SoTA? Do the centers deploy massive shields to protect the electronics?
If radiator temperature is critical you can just run a heat pump to boost it. Modern heat pumps can get pretty close to the Carnot limit for the temperature interval, for example a pump cooling to 300K and dumping out heat at 400K (125°C) will have a theoretical COP limit of 4 and a practical limit of 2.5-3.
That means that for every 3 units of heat your chips emit, you will use a 4th unit to spin the pump. If your panels generate 150kW, you will only have 113kW available for compute and the rest is cooling. Radiators will more than halve vs 340K operation, so it's net beneficial.
It's all a giant techno-economic optimization problem: the extra mass of solar panels you need vs saved radiators vs mass of the pump, the die temperatures you achieve and corresponding performance, durability and chip price point etc.