Why the focus on AMD and Nvidia? It really isn't that hard to design a large number of ALU blocks into some silicon IP block and make them work together efficiently.
The real accomplishment is fabricating them.
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The real accomplishment is fabricating them.
It really is that hard, and the fabrication side of the issue the easy part from Nvidia's perspective - you just pay TSMC a shitload of money. Nvidia's real victory (besides leading on performance-per-watt) is that their software stack doesn't suck. They invested in complex shader units and tensor accelerators that scale with the size of the card rather than being restrained in puny and limited NPUs. CUDA unified this featureset and was industry-entrenched for almost a decade, which gave it pretty much any feature you could want be it crypto acceleration or AI/ML primitives.
The ultimate tragedy is that there was a potential future where a Free and Open Source CUDA alternative existed. Apple wrote the OpenCL spec for exactly that purpose and gave it to Khronos, but later abandoned it to focus on... checks clipboard MLX and Metal Performance Shaders. Oh, what could have been if the industry weren't so stingy and shortsighted.
I guess with money you can win any argument ...
Nvidia's lead is not only cemented by dense silicon. Their designs are extremely competitive, perhaps even a generational leap over what their competitors offer.