Thoughts on software-defined silicon

Thoughts on software-defined silicon

> That makes economic sense when the silicon is broken, and already routinely used with clock speeds or (in the embedded realm) on-die Flash memory.

Except it wasn't broken. The majority of sold chips had perfectly functional additional cores you can enable (back when all it took to enable them was a pencil).

And I'm sure the majority of Ryzen 5 5600X sold today actually have 8 working cores, too. They have fully functional 32MB cache designed for all 4 cores and if your approach was the reason for their existence then we would have had some version of Ryzen with reduced cache and all 8 cores enabled. There are nothing like that because it doesn't make any economic sense: you couldn't fit these between Ryzen 5 5600X and Ryzen 7 5800X. They would be weird side-cousin to Ryzen 5 5600X which would just make buyers confused.

It's exactly the same only now you couldn't sell small percent of chips which are actually defective. But have less SKUs to manage.

I'm not sure if it would work or not, but it makes perfect economic sense.

Yeah, that's what stops these incentives. PR backlash. But as R&D prices for CPUs go up and prices of unused silicone goes down the incentive to switch to that model becomes more and more acute.

Actually the problems with Dark silicon almost guarantee that said model would become the norm eventually.

When you couldn't power all the transistors on the chip simultaneously for thermal reason the ability to pick between features A, B, and C (either of which can be enabled but not all simultaneously) make such scheme pretty attractive. You couldn't do that with millions of SKUs but can easily achieve with million of [potential] licenses.

And in that case the ability to enable features without license would become actively harmful: enabling all features simultaneously would just fry the chip and it would be pretty hard to prove in warranty service that this happened because of customer irresponsibility, not because of customer's misuse.

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