What is the make and model of your computer? The USB driver you needs depends on the motherboard inside your computer.
If it is a Dell go to: http://www.dell.com/support/drivers/us/en/19/DriversHome/ShowProductSelector
If it is an HP go to: http://www8.hp.com/us/en/support-drivers.html
If it is an ASUS go here: http://www.service.asus.com/#!Downloads/c1wax
If it is an ACER go here: http://us.acer.com/ac/en/US/content/drivers
If it is none of the above then you need to find the support site for your computer.