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Laptop: Dell, Windows 7

Desktop: HP, Windows 8

I have a monitor connected to my desktop using a VGA cord. The desktop has two of these VGA ports, so I simply connected my laptop with 1 VGA port to my desktops second VGA port. Both computers were turned off when I did this. I turned on my desktop first (because I want to use it as the computer) and logged in, and then I turned on my laptop. My laptop started to boot up Windows 7 then it made the sound you get when you get to the Windows log in screen but my laptop screen isn't displaying anything. I tried to access the "Display" setting in:

Control Panel\Appearance and Personalization\Display\Screen Resolution

I could not find the second option in the "Display" drop down.

I want to run my laptop screen and Vizio monitor both as dual screens for my desktop

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Most Dell laptop's have a top row of dual purpose function keys. One of them has an icon that looks like a rounded box. Hit that and the function key enable ('esc'?) at the same time to cycle thru the video output choices. One will be to duplicate the view on both outputs (laptop and vga).

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Ok great that fixed my blank screen! But it's running windows 7 from the laptop. Is there anyway I can just utilize my laptop as a screen for my desktop computer? Thanks! – Seth Urquhart Apr 9 '13 at 17:30
Try this: Attach the Vizio monitor the laptop's external video connector (might be VGA only?). At this point the desktop will have no video and will be a headless system. Then from the laptop, remote connect to the desktop. Set the laptop's video output (from the above buttons) to "extend desktop". I think only the laptop keyboard/mouse will be functioning with this setup. If you want to still use the desktop's keyboard/mouse, you can plug those into the laptop. – jdh Apr 10 '13 at 23:56

You can't use laptop as a second screen. One reason is these VGA ports are outputs, not inputs. You can connect monitors to those, because monitors have VGA inputs.

Second reason is that laptop is a computer, which means it will try to boot like every other computer. How would it know that you want to use it as a screen? Before booting OS there's nothing that could handle VGA input (assuming it's possible on hardware level, which is false anyway). After booting... well, then you just have another computer running.

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Alright that makes sense. I've heard it's possible through Remote Desktop Connection so I might give that a try. Thanks so much! – Seth Urquhart Apr 9 '13 at 18:02
Remote Desktop is used for accessing another PC's screen on your screen - i.e. it allows you to remotely control another PC. It's not what you're looking for. – gronostaj Apr 9 '13 at 20:09
I would have to strongly disagree:… – Seth Urquhart Apr 10 '13 at 16:17
That link is to a terribly misleading video. The title and presentation imply that the laptop is a secondary monitor which is not entirely true. What's happening is the laptop's video output is connected to two devices; 1) the laptop's LCD panel and 2) a spare LCD external monitor. (note, no desktop involved). The video has the external monitor configured as the default primary output display and then makes the laptop's panel be the second. This is kind of backwards and confusing. Most people would do the reverse. (BTW The laptop and desktop video connector jacks are for output only.) – jdh Apr 10 '13 at 17:30
Think of the video jack like a water faucet. Trying to connect two faucets with the intention of sending the water back up is not going to work. Instead, the video source (the desktop) needs to create a second virtual video desktop output (as if it was a 2nd monitor) and the laptop would have to connect to that 2nd virtual monitor remotely. X windows in Unix can do this, but I'm not aware of how to (mis-) use windows remote desktop to do this. It's a good question, but its more practical and economical to use a 2nd monitor instead of a laptop. (introduces keyboard/mouse conflicts). – jdh Apr 10 '13 at 23:27

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