Hello Lewis,

I have not come across any resource with all of this information. If the computer case is a pre-built computer manufactured from say Dell, HP, or Lenovo. The chances are not likely that you can replace their motherboard with your own as most of the time their cases are a propritary form factor and proprietary power supply unit.

If it is a white box case, I’m sure you can take a picture of it and do a google image search to determine the make/model of the case which will allow you to research its supported motherboard specifications.

The image below illustrates the screw mount configuration for different motherboard sizes, if the screw mounts line up then you can use that motherboard in whichever case you are looking at.
Motherboard form factor