Win vista/win7/win8 should install the 360 controller automatically. Is it an actual microsoft 360 controller? When you say it's USB, do you mean that it is wired, or is it wired via a plug and play kit? If this is the case you need to purchase a wireless adapter for your PC. You can still use the plug and play charge kit to charge the controller, but the PC will not recognise the controller without the wireless adapter. Hope this helps.