modded xbox360, temp display

Ive recently modded my xbox 360 and now wish to add a LCD temp display, ive got a 12v 4 pin connect free inside the xbox i can use for power but my LCD display i fount and most LCD displays this size all require 5v, however i came across an adapter that can change 12v-5v made for LCD display but im not sure how it all will connect.. links provided below

my LCD display screen...

http://watercooled-pcs.co.uk/en/lcd-displays/lcd-temperature-display-with-sensor-green.html

adapter i fount..

http://www.watercoolinguk.co.uk/p/12V-5V-Reducer-Cable_111.html

im not 100% sure where the two cables on the adapter will connect to?? or maybe there is a better adapter out there? any help would be most helpfull thanks

I don't really understand why you would need this cable - the 4-pin molex as found on 3.5" hard drives and the like already carries both 5v and 12v.