There are a few different ways to open the Device Manager, depending on which version of Windows you are using:  For Windows XP, open the Control Panel in the Start Menu. If you have Classic View enabled, open the System tool. If you aren’t using Classic View, click Performance and Maintenance, then open System. Click the Hardware tab, then click the Device Manager button. For Windows Vista & Windows 7, open the Start menu and right-click on Computer. Select Properties from the menu. In the Properties window, click Device Manager in the left frame. For Windows 8, press the Windows key and the X key on your keyboard. Select Device Manager from the menu that opens. Click the “+” next to the Display adapters category. Your attached video cards will be listed. Double click your video card and use the tabs to find more info about your video card.  The General tab will tell you the model, manufacturer, and if the card is attached properly. The Driver tab will show when the drivers for the card were installed, so you can check if you have the latest version. The Details tab provides specific information about how the card interfaces with the computer.

Summary:
Open the Device Manager. Expand Display adapters. Find out details about your card.