There's not too places you can damage things when installing, but I think the most understated one is the USB 3.0 header that you connect from the case to the motherboard. The plug is super tight and very difficult to remove once you put it in, so I recommend only plugging it in once you're ready to start using your machine. I know too many stories of people breaking it and not being able to plug in USB devices to the front of their PC case because of this.
There's not too places you can damage things when installing, but I think the most understated one is the USB 3.0 header that you connect from the case to the motherboard. The plug is super tight and very difficult to remove once you put it in, so I recommend only plugging it in once you're ready to start using your machine. I know too many stories of people breaking it and not being able to plug in USB devices to the front of their PC case because of this.