Does PR4100 have loud fan? Does Intel CPU have AES-NI?

My experience is the fan is only “loud” when cold booting. It settles back to almost inaudible when the unit is up & running.
Personally, I wouldn’t advise disconnecting the fan. Its there for a reason and also the system may detect a fan failure (disconnection) and cause you other issues!
Can’t help on encryption - Have a read if this thread: