https://www.servethehome.com/120mm-fan-partition-norco-rpc4220-rpc4020/
120mm Fan Partition for Norco RPC-4220 and RPC-4020
Jan 25, 2011 - How to perform the 120mm fan partition for Norco RPC-4220 and RPC-4020 to make the case quiet while still providing airflow
120mm fannorco rpcpartition42204020
https://www.truenas.com/community/threads/build-report-norco-rpc-4224-supermicro-x10-sri-f-xeon-e5-1650v4.46262/page-3
Build Report: Norco RPC-4224, SuperMicro X10-SRi-F, Xeon E5-1650v4 | Page 3 | TrueNAS Community
Will also try relocating the drives to the bottom rows, which seem to have better thermal characteristics. Just been experimenting with the 8TB drives...