Wired Keyboard USB Power problem

Hey everyone, new iMac owner here

Have been sorting out my bootcamped windows, and I have come accross an annoyance.

I have the wired apple keyboard, with the two USB3 ports. In OSX these are powered ports.

HOwever in windows, for some reason, the apple drivers arent working correctly, and they only show up as unpowered ports. This means they wont even load up a standard USB thumb drive, as theres not enough power to read from it. (It comes up with an "insufficient power" popup).

I came across this guide to fixing it in windows:
http://www.youtube.com/watch?v=s8kVWy8Qf7A

However, that shows that the apple keyboard should show up in device manager as "Generic Usb Hub" (around 4mins into video).

My device manager shows it as a USB composite device, and a USB2 Hub (both entries disapear if I unplug the keyboard).

I still tried the fix, forcing the port power to 500 etc, but it didnt actually work.

Also, the guide video shows that the Hub properties page should have mutliple tabs, including "Power" and "Advanced". Mine doesnt have these.

I can only assume the the apple drivers are not installing the keyboard correctly, or that I am missing a necessary USB driver somewhere.

Anyone know the fix for this? I'm on a brand new 2013 iMac, with the current wired keyboard, and windows 7.

Thanks