Where are the 128 bit or 256 bit processors

[mikeredford2011]

Why are CPU's not going to more than 64 bit processors for home or business? I know the software is not there yet either but are they ever planning too. (Windows)

 

[Supernova1138]

The 64 bit address space is absolutely massive as it is, allowing for up to 16 exabytes of RAM. We're not going to be approaching that limit anytime soon on anything except maybe a supercomputer, so 128 bit processors aren't going to be around for a long long time in the personal computer space. Other than expanding the memory address space there really isn't any reason to increase the CPU word size beyond 64 bits.

 

[clubcard]

Firepath is a LIW processor. Instructions are 64-bit but two, four or even eight can run in parallel. Eight means eight 64-bit instructions are read as a single 512-bit block. The main reason this technology (that means you run the CPU slower so no need for cache hence very cheap) hasn't become common is because compilers cannot produce efficient code.
In all likelihood, someone will try to build something like Transmeta's design but make the 'code morphing' visible so while it can emulate 80x86 very well, people can also write native apps. As I said, it is the sheer lack of truly great assembly language programmers left in the field. Everyone moved to high-level languages because the logic was that to speed something up, you just buy faster hardware.
With the IoT firmly on the agenda, I would expect to see a new generation of assembly language programmers. ARM has prototyped CPUs that are printed onto paper.and costing just $0.01 per CPU. THOSE will need the optimization to keep cost down. The ARM1 is now on paper!