the original xbox controllers also used USB so you should be able to wire up ports 3+4 so they can still be used with the original controllers. Also with some soldering you should be able to use the stock power button and eject (use as restart?) and the lights for them. Though you could always just use the wireless 360 controller with the wireless PC adapter.<br><br>

Haven't seen too many original xbox to PC conversions so this should be good to see the way you go about it.<br><br>

Also on the software side if this is going to used as a HTPC, you could always install XBMC and even use a 360 theme if you wanted. XBMC should work perfectly fine with a gamepad and would help fit the theme. I use a Logitech K400, Logitech Harmony 650, and Xbox 360 controller for my HTPC, they offer a vary good experience.