A few months ago, I built an Unraid box following the NKv1(2019) guide. I was able to get a decent deal on ebay for a supermicro x8sil-f with 32gb ddr3 ecc RAM, an x3470, and a heat sink. I put that into the suggested Rosewill Micro-ATX mini case with 400W PSU along with 3 shucked WDs for the array (2x10TB and 1x8TB), 240g sunbow msata in an msata to sata enclosure as cache, and a 1tb silicon power ssd as unassigned for app data. Everything seemed to set up well until I started moving media to the new server. The server will crash and reboot itself randomly while transferring data. It does not seem to correlate to a certain file size or volume of information moving over. Sometimes I can transfer two or three files after another, other times the system will reboot on back to back file copies. I thought it might be due to the janky sunbow setup, so I made the share skip the cache when writing and go directly to the array; it still crashed. I ran a memtest on the memory for 48 hours which resulted in 5 passes with 0 errors. Recently the board has started to make an alarm sound randomly that will last a few minutes, or until the box is rebooted.
Two main questions here.
First, any suggestions to fix my current build issues? It would be nice to be able to use my NAS as a NAS and actually write data to it without it crashing. Is the included 400W PSU powerful enough for the server or could that be causing my issues? Has anyone else experienced the alarm? I found this post on the Unraid forums that seemed to describe the same sounds but does not offer any solution other than removing the speaker jumper on the board.
Second, if I were to abandon this build, what would be a cost effective next step. I would like to reuse as many of the components as possible to save my wallet a bit of stress. The intended uses for the server are a Plex media stack (plex, sonarr, radarr, etc), Unifi controller, and a Home Assistant server.