Computer case

If this is a retail computer case, there are 3 basic sizes:

Micro ATX
Mini-ATX
ATX

You can "usually" install a smaller form factor motherboard in a case.

If this is a case from a name brand computer, your options can be limited. OEM cases are often built specifically for the target motherboard and hardware. They often do not have the standard ATX mounting standoffs, and the I/O shield is typically built into the case.

If you are trying to upgrade a name brand system, it is usually worth the money to go ahead and buy a new case. At a minimum, you are apt to need a new power supply as the supplies in the name brand systems are often low power supplies.

Chas

Chas gave excellent advise, I would like to add to his.

If you know what Motherboard you want to buy, ask the distributer/retailer you are buying from if it will fit in your case. If they do not know, contact the tech support for the manufacturer. This also is advised for memory and hard drive information. Yes, your older hard drives may not work in the new MB without an adapter.

Good luck.

Dad