http://support.acer.com/acerpanam/notebook/2010/Acer/Aspire/Aspire5742G/Aspire5742Gsp2.shtml
Ok , this link is to the Acer support site and gives the specifications of your laptop and if you look under graphics you'll see that there are tow options for that laptop , Nvidia and Ati, now Ati is owned by AMD so the drivers will come from AMD but in the Add /Remove programs it may say Ati drivers or Nvidia drivers.
http://support.acer.com/product/default.aspx?modelId=3278
This is a linkl to the support page for drivers for your laptop and all you would do is choose the Operating System that you have and the drivers for it will be displayed.
You may have to go into the device manager on your laptop and under video or graphics it will tell you which device you have so you'll know which driver to download. Follow the instructions in my previous post.