Ok you have several methods of curing this problem.
1) Go to device manager and roll back your graphics card driver.
2) Do a system restore to a date before you updated the driver.
3) Take the graphics card out and visually identify it. If it is on board graphics look up the motherboard specification and download the correct driver/
4) Use the program Unknown device http://www.halfdone.com/ukd/
to identify your graphics card.
5) Look up the specification of your computer from the manufacturer’s web site.