With 4 Series chipset and Windows 7, support for USB 2.0 ports is provided by the Microsoft standard USB driver. What you need to have installed is the latest Chipset INF Update package (here is a link to the latest version available for your board: https://downloadcenter.intel.com/download/10884/Chipset-Intel-Chipset-Device-Software-for-Discontinued-Intel-Desktop-Boards). This package provides the configuration data that the Microsoft driver needs in order to operate these ports properly.
I am not sure what to suggest. I have seen a similar problem where I plugged a USB 3.0 flash stick into a USB 3.0 port, yet got the "This device Can Perform Faster" message and the flash stick runs at USB 2.0 speeds. I never found a solution to this problem (and couldn't make it occur consistently)...
Sorry I have nothing to suggest...anyone else?
I would recommend going to Device Manager, find the Universal Serial Bus list, expand it by clicking the + sign. Now starting at the bottom, uninstall each USB device that the PC will allow. Reboot and wait for Windows to detect USB and reinstall drivers.
Run Windows Update and I would suggest you to replace the USB cable with a new one.