Hi,
Ah that’s nice, I wasn’t aware that you can manually choose fan speed. For number of workers, if you are talking the number of workers used when creating dataloader, it just refers to how many subprocesses to use for data loading. (See here) There is no formula to chose it to my knowledge. Usually the best choice is related to your cpu (how many cores and how many thread by core).  A typical choice is 8 because many personal computers have 8 CPU cores and one worker thread per core. But if you have different CPU architecture, other values may be better. Note also that number of workers is not limited, you can choose any value you want,  in that case the subprocesses well be waiting in a Pool.