[ash]

Very good article! One of the gems from it:

> If you buy an NVIDIA GPU, you do not get a document explaining the instruction set. It, and many other parts of the architecture, are secret. If you want to write code for it and don't want to use NVIDIA's toolchain, you are expected to generate PTX, which is a somewhat portable intermediate language that the NVIDIA drivers can consume. This means that NVIDIA can completely change the instruction set between GPU revisions without breaking your code. In contrast, an x86 CPU is expected to run the original PC DOS (assuming it has BIOS emulation in the firmware) and every OS and every piece of user-space software released for PC platforms since 1978.