I was recently building a pc for a friend and ran into a problem. We were installing a micro atx board into a full sized case. We couldn't get bottom two standoffs out of the case to move them. We just gave up and ended up screwing the board into the four holes we could. Those holes being the top two and the middle two. There are no heavy components on the bottom and the bottom two screws are pretty close to the middle screws. The graphics card is lined up with the middle screws. I was just asking to make sure it's okay that the board isn't screwed it at the bottom. It seems pretty secure.