CPU importance in a cracking rig

[almandin]

Hi there,

I'm considering building a cracking rig and I'm not sure of the importance of the CPU in a multi GPU cracking rig.

Are there any recommendations on CPU choice when all the hard work is done by multiple GPUs ? Should I buy an expensive one (i9, xeons) ?

What is the work that the CPU typically has to do when cracking hashes with GPU (precomputations, hashtables calculations of some sort) ?

For example, if I buy one ore several 3080 or 3090, will my cracking station will be limited by the CPU at some time if it is not enough powerfull ?

Thanks by advance !