alt Hacker NewsWhy only 45? And why water cooling?
It strikes me that building everything around room temperature or slightly chilled air is a strange choice. This is already 290K-300K or so, and now this is suggesting that things run fine at 320K or 330K?
I've wondered why we couldn't just design everything to operate around 200°C and just use free-cooling by pumping ambient air through. Why don't data centres look more like chicken barns? Do things melt? Are there more errors of some other type at high temperatures?
Replies
joxdosba • today at 10:28 AM
It’d be very hard to make these chips work at 200C, the electrical properties of semiconductors vary significantly with temperature.
It would require entirely different chips with entirely different manufacturing processes.
Semiconducting materials have relatively small band gaps, they are insulators that take very little additional energy to become conductors. In contrast good insulators incinerate before they start conducting (or turn into plasma).
Energy being energy means that high enough ambient heat can kick electrons into the higher orbitals because the band gap is so small. This also happens at normal ambient temperatures, but those electrons don’t make it very far and there aren’t that many. At 200c a closed gate is not stopping enough electrons from moving through it anymore.
At least this is the slightly hand waved technical explanation. Project in Flight on Youtube has an excellent video on how semiconductors work.