Heat not a issue for me, i dont bother with noob mods like slapping fans to cards. I can sort a custom heatsink if needed and machine it to go full length of the card if i have to.
The gen7 microservers onboard sata is rated at sata2 and can't even hit much above sata1 with the drives iv used in it.
A 9211-8i will offer sata3 and does do the full speeds. Pcie v2 x8 slot is enough bandwidth since all 8 drives wont even be on at the same time let alone transfering data simultaneously.
As said before im not the first to attempt it many others run it on serve the home forums etc.
Iv had 6 x 3.5inch drives before in my gen7 and no issues with heat etc since they were mostly 5400rpm drives, os drive was a velociraptor.
Its all well known Avalon doesn't like the microserver but to just tell people to not bother with mods and to go get a bigger proper server is not really what this thread is about.
I try not to judge your random hypothetical questions over various sub-forums, but you’re way off base on this one.
First up - to use your terminology - any noob who has the capacity to machine anything should hopefully grasp that while increased mass and surface area buys you thermal capacity and time to store heat, without airflow to dissipate it, you’re only delaying the inevitable as the ambient case temp increases, you either going to need a disproportionately large heat sink, or significant air flow, as once the case ambient temp ramps up it gets nasty. This is why noobs/people 3D print fan brackets, have you ever put a finger on the heat sink of a LSI HBA while it’s being used in anger? It’s not usually a pleasant experience.
What you state is ‘widely known’ about my dislike of microservers seems to be ignore four minor issues, namely the 4 micro servers I own. My first N36L was maxed out with 10 drives, 4x 2TB WD Green’s, 4x2.5” SSD’s in a backplane (which is exactly what you asked about) and connected up eventually using an old H200 (almost exactly what you asked about) and another two drives for VM pass through. My comments are based on actual first hand experience of what you’re theorising about, just as Armageus' are.
As far as buying a bigger server, did you even read my post? I offered a suggestion about getting maximum performance for minimal cost based using what you have. I use micro servers for what they are good at, NAS duties and light VM/docker hosts. When you start considering making them into something they aren't suited to, anyone with any common sense what so ever would take a step back and consider can you achieve a better result for the same money? Well an H200e is £20, a 2m 8088>8088 mini SAS cable is £6 and a SAS6 disk shelf is £40-120 depending on what you want, they generally take SATA or SAS and don't require interposers (though if you want SSD consider a newer HBA that will support TRIM depending on how you plan on interacting with the drives), my latest SAS6 12xLFF 2U shelves (with drives and caddies) cost me £60 delivered each and arrive later this week.
I got 6 x 3.5's all under 40c and was also tempted to get another broken gen 7 and use it as a DAS with appropriate card so your not alone in wanting to mod if for fun.
Strangely I have walked this path as well, it works, but it's disproportionately expensive relative to the number of drives you get. I'll ignore the HBA as you will need one no matter what and they range from £20 upwards. You need an extra microserver, an 8088 male to 8088 male, an 8088 female to 8087 female and then 8087 male to 8087 male (short) for the backplane to get 4 drives, that's got to be circa £40 in cables for 4 bays, plus the cost of the micro server, lets say you pick up the cheapest N36L sold on eBay sales history (last 3? months), that's another £50, so now you're looking at £90/4 bays or £22.5/bay. Compare that to a £60 12 bay shelf and a £6 8088 to 8088 mini-SAS cable coming out at £66 or £5.50/bay. You drop the micro server cost a bit by just going 8088 to 8087 and passing it through the rear slot, its not as neat, but it is the cheapest option if you already have a broken micro server and just need 4 bays.
This was my fear, I have a few Nvme's kicking around that would be good as boot drive, but ho hum, see if I can get ESXI booting from usb and using nvmes to host systems.
ESXi will boot from a USB without issue, you can then use the NVMe as storage for your VM's as you would normally, this approach works well.