I'm using the touchpad drivers that I downloaded from Dell. On the Devices tab of Mouse Properties, there's a checkbox that says "Disable TouchPad/Stick when a USB pointing device is" (and then it gets cut off, probably by the higher DPI). But, it disables the touchpad automatically when I have a USB mouse attached to my E1705. Very nice for people like me with big hands, or just people who hate touchpads in general.