DELLicious, Refer to the following link: Support for Latitude 5400 | Drivers & Downloads | Dell US The link has the all the latest drivers specifically recommended for the tag 3XKT333. ASMedia USB eXtensible Host Controller is for docking station/stands. Please go to category "Chipset" and update all drivers recommended and also the BIOS and re-test the USB connectivity.  
My USB ports suddenly stop working.  Device manager shows disabled.  Must uninstall and rescan.  This occurs randomly.  I have turned unchecked 'allow computer to turn off power' in the power managment tab.  I have disabled 'selective suspend'.  Problem still occurs.  Is the Intel usb3.0 the correct driver? I noticed on the drivers list for this product that there is an ASMedia USB eXtensible Host Controller Driver listed.   Which driver is supposed to be used for this model? Thanks  
Latitude 5400 Intel USB 3.0 Driver - Randomly becomes disabled