Have you installed Intel USB 3.0 eXtensible Host Controller Driver? [URL]  
Hi I have bought a new Dell Inspiron 5537 and I installed the Win7 64bit. I installed the all drivers from Dell Support but the USB 3.0 doesn’t work. There is a yellow exclamation point in “Control panel -> Device manager, Other devices, Universal Serial Bus (USB) Controller.  Please help me! Thank you very much! EL Masry
Dell 5537 USB 3.0 doesn't work