Driver not drive. A driver is a piece of software that runs in Windows that controls the hardware. Since you installed Windows 7, it does not have built-in drivers for your hardware, so you have to download them one by one from Dell (link given to you by Pyree) and then things will work properly again. The main ones are Chipset (install first), Ethernet, Wireless, Video, Audio, Touchpad. You usually would also want the Power Manager also, Media Reader if you have one.