Diamond-cooled GPUs are coming soon — startup claims 20C temp reduction, 25% more overclocking headroom as it seeks US govt funding for diamond-encrusted chip cooling solutions
Natural diamonds aren't even rar, it's just one big business family owning pretty much every mine on earth. Even jewelry diamonds could be very cheap without artificial price manipulation.
However they'll use artificially produced industry diamonds for CPUs. Since they'll be very tiny and purity probably doesn't matter too much, this is likely a relatively cheap process too. I doubt they'll want to lose on revenue.
It's not as if they're using diamonds hand-mined by children in Africa or something... That's the jewelry market. Synthetic diamond is in a ton of stuff, and it's not really that expensive. The "material" is just carbon.
Excuse me, but they're only diamonds if they come from regions with soil drenched in the blood of child workers. From other regions it's called "sparkling rocks".