2 port back plate, using 2 USB motherboard internal plugs creating 2 seperate busses for windows not to cycle through each port separately every [polling rate/driver latency ] ms

http://www.ebay.co.uk/itm/USB-10-Pin-Internal...Sw~bFWHjIB

USB 3.0 version you need to buy from hong kong

http://www.ebay.co.uk/itm/Sunny-50cm-20-Pin-H...SwcUBYQx2Q