No. A cpu does not require drivers. But, drivers aren't much more than a list of instructions that facilitates usage of a component with the cpu. That component could even be part of the motherboard, like the PCH or Sata controller or Super i/o or part of the cpu itself like the integrated gpu.
So while a cpu as such doesn't require drivers, if you want anything to actually work with the cpu, you will need drivers.
Reinstall windows, whether you want to or not is irrelevant. In layman's terms, right now your pc is set up to speak English, everything communicates in English, all its directives and instructions are in English. When you replace the motherboard, the only language it speaks is Chinese. Everything will have communication issues, performance issues, directions issues etc, and trying to get the motherboard to understand English is about as easy as the motherboard trying to get everything else speaking Chinese. Mostly it'll get by with using sign language, point here and there, but with sign language also exists the possibility of the Universal Finger Gesture, and that can get extremely common.