Since posting part 1 of reducing power, I received the order of my ASRock and have re-used the hard drives from the previous Shuttle I had. The Shuttle wasn’t loud by any stretch, but the ASRock is incredibly quiet. To the point where I have to check it’s still running!
After previously being impressed with how long my hard drives have lasted, one went pop during a power failure. That’s a bit disappointing, but the drives are only Western Digital Blue’s which are just generic consumer desktop disks.