Hi, a friend of mine has assembled a desktop pc for me, at first everything worked well but a few days ago I connected a 2 TB external hdd to the frontal usb port of my pc but suddenly the hdd went so slow that I had to unplug the hdd and repair it using my laptop but since then the frontal usb ports of my desktop pc are no longer functional and when I connect a usb flash drive to the frontal usb ports of my desktop its notification light just keeps flashing and does not get recognized by my desktop and since that day i have to use my rear usb ports. I want to ask what may have caused this problem? and might this issue caused any damage to the motherboard of my desktop? Thanks