[notjoemama]

I’ll add chip designers add redundancy. When errors are detected in testing, they can disable sections of the chip by lasering fuses. That allows routing the circuit through a higher quality area. Quality is measured by not only that the circuit produces correct data but also within tolerances of timing and voltage. IIRC RAM is approximately 10% redundant. A good quality chip will use what meets the spec and leave good transistors unused. A poor quality chip will disable bad ones and only use the ones that meet spec.