USB 3.0 to 2.0 adapter

[Tow]

Hi

I recently bought a case with usb 3.0 front panel, however, the motherboard I use (I plan to upgrade it later) only has 2.0 USB. I decided to make my own adapter even though there are many options on amazon and newegg since the adapter is only a bunch o cables.

 

Looking to the datasheets of both 3.0 and 2.0 pinouts, I stumbled upon a pin called NC on the 2.0 that I don't know where to connect. I guess it goes to ID on the 3.0 but I don't want to damage the front usb ports or even worse the motherboard.

 

Does anyone know where that connection goes?

[Tow]

HI, I mistankenly posted this on the wrong forum.

 

I have already re-posted it on the correct (hobby electronics)