This seems awfully wasteful. One of the main reasons for which I've built my own homeserver was to reduce resource usage - one could probably argue that the carbon footprint of keeping your photos in the cloud and running services is lower than building your own little datacentre copy locally and where would we be if everyone builds their own server, then what? Well, I think that paying Google/Apple/Oracle/etc whoever money so that they continue their activities has a bigger carbon footprint than me picking up old used parts and running them on a solar/wind only electricity plan. I also think I'm going a bit overboard with this and I'm not suggesting to vote with your wallet because that doesn't work. If you want real change this needs to come from the government. You not buying a motherboard won't stop a corporation from making another 10 million.
Anyway, except for the hard drives, all components were picked up used. I like to joke it's my little Frankenstein's monster, pieced together from discarded parts no one wanted or had any use for. I've also gone down the rabbit hole to build the "perfect" machine, but I guess I was thinking too highly of myself and the actual use case. The reason I'm posting this is to help someone who might not build a new machine because they don't have ECC and without ECC ZFS is useless and you need Enterprise drives and you want 128 GB of RAM in the machine and you could also pick up used enterprise hardware and you could etc...
If you wish to play around with this, the best way is to just get into it. The same way Google started with consumer level hardware so can you. Pick up a used motherboard, pick up some used ram, a used CPU, throw them into a case and let it rip. Initially you'll learn so much and that alone is worth every penny. When I built my first machine, I wasn't finding any decently used former desktop form hp/lenovo/dell so I found a used i5 8500t for about 20$, 8 gb of ram for about 5$, a used motherboard for 40$, case was 20$ and PSU was $30. All in all the system was 115$ and for storage I used an old 2.5inch ssd for boot drive and 2 new NAS hard drives (which I still have btw!). This was amazing. Not having ECC, not having a server motherboard/system, not worrying about all that stuff allowed me to get started. The entry bar is even lower now, so just get started, don't worry. People talk about flipped bits as if it happens all day every day. If you are THAT worried, then yeah, look for a used server barebone or even a used server with support for ecc and do use ZFS, but I want to ask, how comfortable are you making the switch 100% now over night without having ever spent any time configuring even the most basic server that NEEDS to run for days/weeks/months? Old/used hardware can bridge this gap and when you're ready it's not like you have to throw out the baby with the bathwater. You now have another node in a proxmox cluster. Congrats! The old machine can run LXCs, VMs, it could be a firewall it could do anything and when it fails, no biggie.
Current setup for those interested:
i7 9700t
64 GB DDR4 (2x32)
8, 10, 12, 12, 14 TB HDDs (snapraid setup and 14 TB HDD is holding parity info)
X550 T2 10Gbps network card
Fractal Design Node 804
Seasonic Gold 550watts
LSI 9305 16i