Hello, My question is about the CPUID opcode that has been a part of the x86 instruction set for many years now. I'm familiar with the paradigm: Place certain bytes in the EAX register and possibly also the ECX register and the CPU will return info in general purpose registers that is meant to be interpreted bit by bit to determine whether the CPU possesses certain features. My question, though, is where is this info permanently stored? I have a diagram of all of the registers used in modern x86-64 CPUs, and I can't find a ROM register anywhere that holds information. Is the info held in non-volatile RAM where the BIOS parameters are stored? Thanks.