Any rackmount server will be a nuisance. I ran rack servers at home for years but recently replaced my servers with ATX form factor machines, which are super quiet, ventilate much better and still stack nicely. There are plenty of ATX Xeon motherboards that support ECC ram.
I won't be the first to admit that the rackmount hardware is a nuisance, but at the same time, it's relatively inexpensive since there's no practical reason to buy new hardware for a homelab and the IT renewal companies are absolutely overflowing with reclaimed hardware on the cheap. Also it's often easier to find hardware configurations that require no tinkering at all, verses having to slog through a PC build and hope that nothing goes wrong. My favorite hardware though are workstations and tower servers, since they're basically the best of both worlds - commercial machines with a decent amount of replacement parts with tool-less (or even hot) swapping and people with experience servicing them while still being fairly quiet at heavy load.
I've done it every other way - I have a dual chip Xeon Silver machine that I hand built, an IT reclaimed Dell rack server, three NUCs (used to be 4 but one bit the dust after 4.5 years of hard service), and a smathering of other hardware (NASes, 10G and 1G switches, etc.)...
After the absolute pain of the Xeon Silver build - having a brand new motherboard that was DOA and basically being told I was out $600 after multiple rounds of escalation, then having the replacement board fight with my GPUs, I'm not sure if I'm willing to bother doing it again. It would have been worth it to pay the markup on a gently used commercial machine and I would have been up and running faster... Probably would have been cheaper, in fact.
Yeah everything you mentioned is spot on. I wish I had a garage to operate all my equipment, but have to work within the constraints of my small apartment.
Depends on your storage needs. More than 6-8 hard drives and getting an ATX form factor machine is near impossible, while many brands/generations of rack mount servers fit the bill for cheap.
SAS are better, but for my NAS/Media server needs I use SATA. I have 8x8TB, 2x4TB and 1x500GB SSD...all within a 2U rackmount server that set me back less than $250 that includes things like backup power supplies and 192GB of RAM. I bought another 1U rackmount to run my personal website and NVR (Zoneminder).
I haven't tallied all the costs...nor do I want to.
The media server is an 2U HP G8 DL380P with the 12LFF drive cage. I run Xpenology (synology hacked to run on other hardware). That allows me to run Plex and Docker along with some auto backup stuff from my other computers (also serves as a central point for VM images to roll out to my computers depending on which I am using that week). I was incorrect about the RAM, this server is only 48GB since Xpenology can't use it all. Server has dual E5-2440s.
The other server/NVR is a 1U HP G8 DL380e that has a 4LFF drive cage. Came with the 4x2TB setup already and it's running Ubuntu server 20.04. Zoneminder is a great software package and easily handles my 8 1080P or better PoE cameras around my house/shop. I think it was also ~$250 on ebay...with another $50-60 in RAM from eBay (Zoneminder does a lot of caching in RAM for prior to recording movement detection). This machine sports 192GB of RAM and dual E5-2650s.
That’s right, though 4U cases generally only ventilate from the front and back, which seems to contribute to their noise level. I figure that only a small minority of the 4U market runs their servers in apartment kitchens.
I’ve had good luck using horizontal Silverstone ATX cases with fans on three sides. That said, I’m sure there are 4U units that offer huge but low rpm fans that would satisfy the bedroom server-lab niche market.
I guess I've never owned a tower that ventilated on the top or bottom. I don't like top fans because gravity means things get in them, and bottom fans don't work on carpet.
Usually 4U cases have a lot of fan mounts so rather than a few large radius fans you have lots of small radius fans. It used to be that all small fans were loud but in the past decade or so you've been able to get smaller fans at just about any noise point you want.
