So, update on what's happened so far. I got everything except the HBA card, and finished building this. When The HBA card arrived, I installed it and...... no disks.... so I was a bit annoyed / surprised. After fiddling a bit around, I found out that this card only works well if you have it running in a mode with the motherboard which allows *also* legacy settings. For some reason, no matter what I did, or how I tried to firmware update it, it did not wanted to be recognised.
It looked to have worked on a different system, but in the end I can't get it to work with the current system. So. Now I have ordered a new card, and will be looking forward to when this arrives. I ordered the Dell PERC HBA330 PCIe 12G HBA (0J7TNV) as a replacement, which should arrive tomorrow.
To test if the disks were working, I still had an old Areca RAID card lying around, and it looks that the disks are being seen by the devices (although it also looks like the RAID controller doesn't support these sizes 🤣).
So, for now: I need to wait until the package is delivered and I hopefully have a happy NAS at that moment.
Once everything is finished, I will post my final build & screenshots, as well as a full (sort of) step by step on why I choose things, and how I have build it.
I will update once I have an update on this!