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My desktop computer has one VGA port. Can I use a VGA splitter connector to add another monitor as an extension of the first monitor instead of duplicating the first monitor, or can I use a USB To VGA Adapter to have an extension of the first monitor?

The computer also has an HDMI port. Can I use it to connect another monitor as an extension of the first monitor? and do I need a HDMI-to-VGA Adapter?

Thanks for any helpful answers.

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A VGA splitter will likely duplicate the image onto both monitors. A USB->VGA adapter would allow you to run 2 the second monitor as an extension instead of a duplicate. The USB adapters can be specific about the resolutions they will support so make sure to get one that matches the monitor resolution.

Alternatively, Buy a cheap 2 output graphics card (will likely be cheaper than the USB->VGA adapter anyways) and run both monitors off of a proper dedicated card.

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It all depends on your graphics card.

Given that you've only got one VGA output it's highly likely that it won't have enough memory or processor power to handle multiple monitors.

You'll need to find out what make and model the card is and see if there is a driver that will cope with multiple monitors.

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Chris, but there is a HDMI port in the back of the computer box and here is the hardware configuration of the computer:…, can I use that to connect a monitor? and do I need a HDMI-to-VGA Adapter? – user51210 Oct 3 '10 at 22:54
@user51210 - Possibly. Sorry I'm not giving you a definitive answer. – ChrisF Oct 4 '10 at 7:56

Yes. You can connect one monitor to VGA & another to HDMI. If the monitors themselves are VGA & HDMI respectively, you won't need any additional adapters.

Before you go buying any monitors, make sure your OS is recognizing both video cards. It's possible the one you're not using has been disabled in BIOS.

Once you have both screens plugged in, you'll just need to change your display settings in the OS to enable access to the second screen (and set options like resolution, and where the 2nd screen is relative to the 1st one).

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