Amphium wroteListing says micro atx for me
I reckon he means his motherboard, not the case he linked.
Tasty wroteThe two most common SFF sizes are Micro-ATX and Mini-ITX.
In DIY builds, yes. Dell and HP are notorious for using proprietary components though, especially weird proprietary form factor motherboards(like BTX and uBTX). Shame really, makes stuff like this a nightmare.
Tasty wroteThat being said, the case you linked is Micro-ATX, so it should be able to accommodate everything just fine
Up to mATX. ATX and "EATX" will of course, not fit, just to clarify.
Tasty wroteI'm guessing there are multiple versions and generations.
That would be correct. As far as I can see, there are "Inspiron 3471"s with CPU's up to even Intel "9th gen", and I imagine there are some with CPU's as old as Sandy Bridge(2nd gen).
OP - Download Speccy, HWMonitor, HWInfo64 or any other monitoring tool. These should give you more specific information on the components inside your system. You should be able to get the make and model number of the motherboard, or at least some information about it.
If you post a screenshot of one of these monitoring tools, or list the specific components in your system, then we should be able to actually help you. Currently, we've not got enough information to help at all(Dell's fault in this case, not yours).