Hi,
Uninstall and reinstall ‘Display Adapter’ drivers. Refer the following step:
a) Start Control Panel, click Hardware and Sound, and then click Device Manager.
b) Expand the node that represents the type of device that you want to uninstall, right-click the device entry, and click Uninstall.
c) On the Confirm Device Removal dialog box, click OK to start the uninstall process.
d) When the uninstall process is complete, download the drivers from the manufactures website and install the drivers.
e) After installing the drivers, install latest updates.
http://windows.microsoft.com/en-US/windows7/Update-a-driver-for-hardware-that-isnt-working-properly