Just another note: the ones that mount to the back of the bracket sometimes (depending on your card design) sit underneath the heat sink shroud. Some cards have very flimsy plastic shrouds around the fans, which can warp over time and cause your fans to run into the shroud. So if you have such a card (I have a couple of old 270x's like this) make sure you get a very long bracket so that it distributes the weight across the entire card, and not only along the "back" side of the card. Some of the cheaper brackets are short and only hold up the back near the IO brackets... If you don't have a backplate on your card, those aren't even worth it, as they just allow the card to sag at the middle. Get a long one, at minimum 3/4 the length of your card. (And that's solid advice for any card, regardless of the shroud, though if it has a good backplate, that can alleviate that issue.)