I have a very short equipment rack installed in my server closet. It is only 16 inches deep, fine for most networking uses, but not great for most rack-mount server cases.
I am looking for case suggestions that would fit my rack, 16 inch depth maximum. Height isn't a problem, the rack has a ton of vertical space, over 15U, it's the depth that's an issue.
I've looked all over the Internet for <16" short-depth cases multiple times over the years, and I've learned the most important question is this: what do you want to put in it?
I'll tell you right now that some of the things I've wanted, like...
A 2U with hot-swap caddies all the way across the front (like this or this, but <16" deep at the cost of fitting only an ITX motherboard), or
A 4- or 5U chassis that can fit an EATX / SSI EEB (12"x13") motherboard and an ATX PSU at the same time, or
A chassis of any size that has both the motherboard/PCI I/O and the drive bays on the front (front drive bays are normal and you can get front access I/O, but not both at the same time)
...simply do not exist, as far as I can tell. I'm pretty sure all of these things are geometrically possible (I did the math), but apparently I'm the only one who wants such weird stuff.
You can get a basic-bitch whatever-U case that supports a mATX motherboard and hard-mounting a couple of internal drives, with sharp metal edges, a shitty plastic door, and a price double (or more) what similarly low quality would cost in a desktop form-factor all day long, though.
Yeah, seems like there isn't a big group of folks that are looking for this kind of solution.
I've thought about designing a case to my specs that could be 3D printed or maybe be built with some very basic steel sheet, but that's more DIY than I have time for right now.
I recently hunted for a rack mounted case for an ATX MB and PSU. The best I could find is 17.9" deep. Is your rack's rear end closed? Any way to remove the rear panel? There is a site that'll make you a custom rack mount case I came across. But it was mighty pricey.
Back end is open but wall-mounted. If there is a way to mount the case forward a few inches so it leaves a gap in the back, that would be fine with me.
I haven't found any brackets that seem to do that though.
These guys do short depth PCs. I wish I knew where they got their cases from, because they are really nice!
But I haven't found anything decent in the wild (I eventually gave up and got a deeper rack so I can use old r730 servers)