@rpardee
That case design is a horror show. Standard practice for Dell, though.
I don't see any good place to mount a 3.5 in HDD.
If I were you, I would park that drive right on top of the power supply, with these under the 4 corners to reduce vibration and to keep it from scooting around.
https://www.amazon.com/Moongel-RTOM-Resonance-Pads/dp/B00GXNZP80/
@voltronic Ah--thanks for the advice! I suppose it may come to that. :( I wonder if I wouldn't be better off just buying a housing for this thing & running it as an external drive... Tho then I guess I have to power that separately (right?). Probably a PITA.
Amazingly, the new machine is pretty light, tho I totally take your point...
@voltronic ah, bummer. I do have one USB-C port, tho it's on the front of the machine, so less desirable.
I'll do a little more research to see if I can find something to actually screw the drive into & if not will go w/your idea of perching it on the PSU.
@rpardee
It will actually be superior to hard-mounting the drive anyway, as long as this system is staying in a fixed location.
Hot glue it to the PSU enclosure.
@FreedomATX
Uh, I hope you're kidding.
Depending on where the glue goes on the enclosure, I'd give it as high as 50/50 that the glue stays solid during use!
@rpardee
If there is an eSATA port on this motherboard, then maybe. I doubt it has one. USB will be much slower so I don't recommend it unless it's USB-C or if you need this to be a portable drive.