Thoughts on software-defined silicon

> The reason for this is because defects happen (semiconductor chip joke for free, right there). If you have a problem in a redundant part of you chip, you can close it off and sell the rest of the perfectly good chip at a lower price point. Or lower the clockspeed, whatever.

As I pointed out elsewhere, the degree to which this happens is greatly overstated by semiconductor companies. True, not every chip is going to reach the full clock speed and have all cores working. But for one, especially on mature nodes, the majority of them do and also that doesn't apply for many other lines they already segment along like maximum memory capacity, ECC, software features like Ryzen PRO/vPro etc. The far majority of chips are cut down because they wouldn't sell at a higher price, not because they are defective in any meaningful way. They do this because relatively speaking, the individual chips are dirt cheap (tens of dollars), all of the cost is in the NRE.

> So now you have to track the certs for your chip in _addition_ to the chip itself! Alternately, maybe it stays once enabled sweet, now you have to track the _variants_ of the same chip.

It is generally rare for a cpu to leave a system after it gets put in and tracking per-device licenses already needs to be done for all of the other hardware like switches, BMCs, etc. so it's not really a lot of extra effort for them.