How to Enable Dual Monitors With VGA and DVIby C. Taylor
Windows 7 natively allows a dual monitor setup, which extends or duplicates your display onto both monitors. It does not matter if one monitor uses an analog VGA interface, and the other uses a digital DVI interface. As long as both monitors are functional and connected to your computer, you can use them for your dual monitor setup. This setup can greatly improve your productivity, especially when your work requires multiple windows open simultaneously.
Connect a VGA monitor cable from your computer's VGA port to your VGA monitor. If your computer only has two DVI connections, use a DVI-to-VGA adapter to convert one of the DVI ports on your computer. This is a simple adapter that attaches between your VGA cable and the computer's DVI port.
Connect a DVI monitor cable from your computer's DVI port to your DVI monitor. If you need to convert a VGA port into a DVI port, you can use a VGA-to-DVI converter. However, these powered converters are considerably more expensive than a DVI-to-VGA adapter.
Plug both monitors into a wall outlet, power them on and boot your computer.
Right click an empty area of the desktop and select "Screen Resolution."
Click the "Multiple Displays" drop-down menu and select "Extend These Displays" to extend your desktop across both monitors. Alternatively, select "Duplicate These Displays" to show the same graphics on both monitors.
Click "OK" to enable dual monitors.