alt Hacker NewsChip fabrication processes are not fungible: GPUs and CPUs might be made on roughly the same process, but DRAM is not (flash is a different process again, as is power electronics, analog electronics, MEMS, etc. And even within those broader categories there are different variations). While there are some overlaps in machines and techniques, a fab set up for one cannot generally switch to the other, and the economics of each process can also be drastically different.
You're not the first person to say so (and I don't mean to dispute it), but I have never been able to find a clear answer for /why/ those processes are incompatible.
Is it built in different silicon, is it physical steps that's incompatible (ie its actually incompatible), is it different physical preparations that needs to be made (making it economically infeasible to combine)
I cannot help but wonder, even if the answer doesn't change anything in my life.