Triple-monitor set-up (2 unique, 1 cloned): Can a VGA splitter be used on one output of a dual-head

Posted by stakx on Super User See other posts from Super User or by stakx
Published on 2010-03-31T12:51:42Z Indexed on 2010/03/31 13:03 UTC
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Background:

I'm currently researching hardware components for some kind of information terminal we're building.

This application of ours makes use of three output screens:

(1) A touch screen where all user input is made;

(2) A regular LCD monitor where the requested information is being displayed; and

(3) A projector which displays exactly the same signal as screen (2) does.

(All screens will run at the same resolution of 1024x768 btw.)

Now I figured that using a dual-head video card would be sufficient, let's say a Matrox P690 low-profile PCI card. This would involve having a Y cable connected to the graphics card itself, then two DVI-to-VGA adapters at each end of the Y cable, and then having a VGA splitter on one of the VGA outputs.

The following shows the setup in question:

0--1---------2-> VGA (DSUB-15)
    \
     \
      ----2-3---------> VGA (DSUB-15)
             \
              \
               -----------------> VGA (DSUB-15)

0: graphics card (LFH60 jack)
1: LFH60 to DVI-I dual monitor Y cable
2: DVI-to-VGA adapters
3: VGA splitter cable

Question(s):

Will this work? I'm particularly concerned about the following points:

  • Can a low-profile PCI video card output a signal which is strong enough for three monitors (even if it's a dual-head card)?

  • Does the combination of so many adapters and splitter cables work? (The LFH-to-DVI cable comes with the video card)

  • Will the VGA splitter cable degrade the signal on the output screen & projector significantly? (If so, would a USB-powered splitter cable remedy this problem?)

I can't possibly expect anyone to answer all those questions, but any input is appreciated.

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