I've never seen anyone mention this before. Is this really in the cards? Or are all the extensions patented as well, so that a hypothetical Apple (or whoever else takes it on) x86 wouldn't be able to use x86 without licensing it?
Author has clearly not heard about NexGen! They implemented a RISC architecture that code morphed x86 i586 design. They were then bought out by AMD who shortly thereafter adopted the design for their own architecture. Then Intel had no choice but to adopt NexGen architecture as well lool. We all use NexGen Architecture now. The most famous microprocessor no one's heard of. I only know because NexGen was based in Milpitas and that's where I live, so Milpitas Architecture is like hometown pride.
As for patents, Xed is tiny (only ~4kb) and it allows us to distinguish the which instructions belong to which microarchitectures, e.g. k8, sse3, sse4, avx. That gives us a clear accurate picture of the intellectual property rolloff, thereby enabling a fabless chip or emulator to simply ignore the encumbered parts of the encoding space. The tradeoff is you can't patent troll Intel (due to Xed being licensed Apache 2.0) and I think that's fair.
Quake was just starting to ignite the world and pentium performance at 486 prices would have done more, but no fpu... it ran NT fine enough although my memory wants to say Microsoft detected it as a 386 so that would have cut NT 4 out of the picture.
I thought knowledge of them was more common but I guess not
Devices that run Windows 10 for desktop editions require a 1 GHz or faster processor or SoC that meets the following requirements:
* Compatible with the x86* or x64 instruction set.
* Supports PAE, NX and SSE2.
* Supports CMPXCHG16b, LAHF/SAHF, and PrefetchW for 64-bit OS installation
If Intel had a patent on this, it must have been on some (possibly tiny) variation, though, as IBM had register renaming in hardware in 1967 (See https://en.wikipedia.org/wiki/Tomasulo_algorithm) and the POWER1 had it in 1990.
I think the sibling comment is more accurate: while the core of the ISA might effectively be public domain soon, there are plenty of extensions in common use that aren't. If you implement a custom x86 design without those a lot of software won't be able to run or it will run with significantly worse performance.
I'd be interested in being pointed to any references as to what they've actually done, not that much information is likely to be public domain.
And it makes sense for them to do it too, they clearly have the money and people to pull it off and it gives them a big competitive advantage. It's not for nothing that they push for ARM on the desktop as well, this way they'd have a tighter control on their ecosystem than they've had for decades (maybe ever), both soft- and hardware.
Yes. So, if you want to reimplement a CPU from 1999, you will probably be fine without any kind of license. If you want to add features or use new methods, however, you may run into infringement issues.