PCIe slots don't just break without significant external force, such as a full system being thrown around during shipping with inadequate internal packaging. People have been using aftermarket coolers that are a lot larger and heavier than this thing for a long time (some of them end up taking up about five slots once you add fans). Hell, even some high end Turing cards are about as large as this is. The fact that it's held in via a true triple-slot I/O plate and three screws means it'll put less strain on anything than a lot of the huge "2.5" slot cards do that only secure with two. Motherboards are a lot stronger than people think anyway. I remember when people used to make the claim that huge tower air coolers would snap your motherboard, yet I've literally never heard of it actually happening.