Gregory's Server
The XOR (exclusive-or) gate is a logic gate that produces a 1 if one input or the other is a 1, but not both. This is useful for adding, flipping bits, and other functions. XOR is harder to implement than other gates, so chips use a variety of ways to implement it. 3/9
For the 386, Intel started using standard-cell logic. This is now common but was a big step at the time. The idea is that each gate has a standard circuit in a library so a computer can automatically wire the circuit. Faster than manual layout but the rows waste space. 4/9