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I have two computers here (A and B), and i would like to view computer A display on compter B. I'm aware that this can be done via VNC but its too slow. I am wondering if there are any cables+software available that will capture the video output from computer A and convert that to a USB video input for Computer B. Something like a VGA (or DVI or HDMI) output to USB input converter.


marked as duplicate by Ƭᴇcʜιᴇ007, Gaff, Tog, HackToHell, Renan Feb 25 '13 at 12:58

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  • Why don't you try remote desktop software or something that comes default with Windows? (I've never heard of what you're asking for, but that's what I'd do) – cutrightjm Feb 25 '13 at 4:41
  • Also, what would you use this for? You want two monitors, mice, and keyboards that can control the same computer? – cutrightjm Feb 25 '13 at 4:50

You are looking for a "vga capture card". Googling that returns a large number of results. A software-based solution (not necessarily VNC) using a wired network will probably be cheaper and better.


I Don't think (video) to USB is going to be particularly practical, or produce an accurate picture with less resource use then VNC or equivalent (because VNC can at least optimize the output by telling it to "draw a box of this color" and recreate a screen, rather then capture it. Similarly 100 megabit ethernet is faster then USB2 and gigabit ethernet is faster then USB3.

Have you tried enabling compression for your VNC stream and reducing the color depth ? This can make a HUGE difference in performance (particularly compression, and if you don't do "wasteful" things like have an image background). Also, you haven't advised what OS's you are running - there may be more bandwidth effective variants on VNC (like RDesktop, exporting your X Session)

You may be able to get a VGA -> H264 or MP4 Video capture and then play that back through your second monitor, but I see a few problems with this, including detail will be lost in the lossy compression, you will need more CPU/GPU to decode the screen as well as expensive hardware to encode the stream. I suspect by the time you are finished it would be cheaper to get a second monitor and long VGA cable.


If the computers are near each other, then use a VGA switch. It is a device that allows using a single monitor with two or more computers. This should be more practical. Another option is, a KVM switch (shares monitor, keyboard and mouse). As a last resort, assuming one of the graphics card provides TV out, is to fit a TV tuner in the other computer and use it to display the first computer's screen in a Window. Of course in PAL mode you are limited to 800x600 (NTSC is worse). I did it when fixing old PCs and had no second monitor, so I used my Pinncale PCTV Pro for that.

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