Ever since I first build my computer, I could never get my Rear IO to fully line up with the shield, the top most ports (Being 2 USB 2.0 and a PS2 port). When looking at the back of my PC when fully built, the ports are leaning to the right, making the IO shield get in the way.
I'm using a G1.Sniper M5, and my case is an Obsidian 350D.
(And yes, I hate my motherboard, because of poor linux support, Atheros NIC, and Audio Drivers, planning on fixing all that when I upgrade to Skylake)