This was my original FreeNAS build, when I first transitioned away from MD arrays in my desktop PC to a dedicated storage appliance.
The Fractal Array R2 case was a complete pain to work with & wouldn't even accommodate a half height HBA without using a Dremel to cut out part of the drive cage.
Built around the Intel Server Board S1200KPR, which was the only Mini ITX board with ECC support at the time, with an IBM ServeRAID M1015/LSI SAS9220-8i flashed to IT mode for use as a HBA.
I eventually transplanted all of the components into a tower case, then ditched the Mini ITX board for a Supermicro X10SLM-F as I needed additional PCIe slots for a 10GbE NIC & a USB3 controller for snapshot replication to an external drive.
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