Noob questions on a first build (SuperMicro chassis & asrock470du)

[fatefree]

Hi guys, I am building a homelab do-it-all server (nas, plex, dev, home automation) and there are a few things I can't seem to find a reliable answer for.

The relevant specs are:
Ryzen 3900x
ASRock x470du
SuperMicro 3u with BPN-SAS2-836EL1 backplane

I've only ever built desktop machines before, and this would be much easier with a regular case, but I hear very good things about the supermicro chassis so I'd love to use that. I just don't understand two things:

1) How do I connect this backplane to the motherboard? I won't be using all 16 drives at first, and they are primarily for media storage. Do I need to buy an HBA-SAS connector? What specs do I need or what would be recommended? Do I have to purchase extra cables as well?

2) How does the SuperMicro's PSUs come in a used case? Do I need to buy a set of cables to power everything?

3) With all the bad posts about that ASRock x470du in that mega thread, is there an alternative I should consider? Is ECC Ram support important for this server to protect my data?

I'd appreciate help with any of the above, specifically number 1 since I'm lost there. Thank you!

 

[artlessknave]

1. any SAS HBA, commons ones are LSI 9211/IBM 1015/dell Perc h200/h310, in IT mode. about 30-70$. be cautious if buying from ebay, there are tons of counterfit LSI cards being dumped from china. there are more expensive options, any of which are fine as long as they are in IT or HBA modes. SAS3 will work with the sas2 backplane but be kind of a waste, and might need a sff8463 to sff-8087 instead of 87-to-87.
that backplane is SAS2 (-SAS2-), and it's a single SAS channel expander (EL1). you would connect the 2 sff-8087 ports to the 2 upstream sff-8087 with 2 sff-8087 cables on the backplane. and that's it, everything is connected, tho power is separate.

2. the SM PSU's are usually hotswap, which means the PSU itself is modular, the cables are attached to the PSU cage and basically are part of the case. you should only need separate cables if the case cables dont have what you need, but that should be unlikely, since the PSU cage is made for the case. chances are good the backplane would already be plugged in to power.

3. ECC is ALWAYS important to protect data. it makes sure everything written and read is accurate.
also, that board states it only supports ECC with PRO ryzen for certain CPU ranges (ECC requires both board AND CPU support for it), and it doesn't look like the ryzen 3900's have ECC on the AMD spec page. supermicro boards are HIGHLY recommended, for the same reasons the chassis are so highly recommended.

you can check out my sig for the hardware I use, and there is a link to loads of useful links