USB disabled no OS

Hi all,

I am trying to build my own PC.

I've done something pretty stupid in order to try and boot Windows 7 via USB and use USB keyboard and mouse while installing.

My motherboard is an ASUS Saberbooth Z97 mark 1.

I was trying to disable USB 3.0 functionality so I could use 2.0, as I understand Windows 7 installation media does not support it.

In doing so I appear to have completely disabled all USB ports rendering any input I had to the computer redundant.

To my knowledge all ports are USB 3.0 but with backwards compatibility. I'm really stuck can anyone tell me how I can get back into my computer?

Currently it boots not recognising the mouse or keyboard and goes into the UEFI screen but i cannot use the mouse or the keyboard to amend anything.

I haven't found building easy and this is another low point..

Thanks for any help or advice you can suggest.

Regards

John