problem with the usb 3.0 speed

im using pavilion g6 2016 tx windows 8.1 pro,

when im using windows 7 i used to get about 38 MBps speed ,but after installing windows 8.1 it wont exceeding 32MBps..

but once i got 70 MBps for an avi video..only for that video..

here is the screenshot of my usb drivers ..Image may be NSFW.
Clik here to view.

can anyone help me...