Looking for the fastest, most awesome video card... that'll fit a 3U case

Here's a fun one for you guys. We all know what the fastest video cards are, but I have a 3U case that probably won't take those. I am looking for a consumer level video card (AMD or Nvidia) that will fit inside a 3U case. Length is not an issue, but the height is. The power connector(s) cannot be facing the lid/side panel (3U clearance here). Also, the heatsink and shroud can't be so gargantuan that it extends more than a couple millimeters past the expansion bracket. That pretty much eliminates the video cards with showy heat pipes (or whatever you call those). Currently, I have an r9-270x. is there anything better that'll fit?

Thanks