But the cutout doesn't always line up with the CPU socket area.
You may need to install a large backplate that has to be mounted behind the motherboard, which you should do before installing it in your case. Many cases have cut-out sections behind the motherboard area to allow for adding a CPU mounting plate after the motherboard is installed. But the cutout doesn't always line up with the CPU socket area. And holding a metal plate in place behind the motherboard while you add mounting hardware inside the case requires a lot of dexterity and patience.