So I had a problem with my USB 3.0 controller in Windows 8.1. I had hooked up a Kensington USB 3.0 Dockingstation and this worked correctly, until I started some GOG games (Clive Barker’s Undying) that ran on old 3DFX graphics. The screen started to flash (blank to black) intermittently when the game were started. So I tried to install “updated” drivers, using this post. But that failed somehow, and this showed because now my USB 3.0 controller was completely missing in Device Manager. I tried reinstalling from the Intel website, but that failed with “minimum requirements not met” errors, and compatibility changes also did nothing, while the Windows 8.1 Installation DVD also failed to be helpful. Finally, I used AIDA to check the chipset, and lo and behold it came up with Intel Panther Point PCH – USB 3.0 xHCI Controller. The intel website was not supportive, but I googled it and found drivers with that name. These to be precise. Those installed and immediately the Kensington stuff reinstalled itself automatically! Huurah!