Windows 10: Dual Monitor Y-Cable Solved

  1.    21 Nov 2015 #1

    Dual Monitor Y-Cable

    I did, some years ago, implement a couple of dual monitor solutions with Dell machines using a Y-Cable provided by Dell (using a DMS59 socket on the computer). I'd like to do that at home now.

    I have a Radeon 7850, which has a fully populated DVI-I-plug (i.e. two monitor signals). I want to buy a DVI-Y-cable, connect two monitors to it, and let Windows 10 (1511) create a Desktop which spans these two monitors (monitors have same resolution and frequency).

    Now, I read on Amazon a lot of talk that you actually cannot do that with a Y cable, you can only have the same content on both monitors. Which is the opposite of what my own experience tells me, and also seems unlogical, since there are two fully equipped data channels which can provide a horizontal resolution of at least 2560 pixels, and I have done this before, a few years ago, and it worked.

    Can anyone please she some light on this for me - am I missing something? Can this be done with my graphics card and a Y-cable, or do I need some sort of active box which splits the signals onto two monitors for me?

    Thank in advance for all comments!
      My ComputerSystem Spec

  2.    21 Nov 2015 #2

    What makes you think the content is different on the Analog vs Digital lines of a single socket?
      My ComputerSystem Spec

  3.    21 Nov 2015 #3

    Nothing. But looking at the pin layout of a DVI plug, there seem to be two complete digital data channels in it, and I thought Windows or the Grafix card drivers can somehow work with that. The analog part is the 4 pins in a square layout on the side right ? That is not what I was referring to .

    If I am entirely mistaken - then what do I have to do to get an extended W10-Desktop across two monitors? I know what I have to do in Windows, but how do I have to connect the monitors? Or do I need a graphics card with two separate DVI sockets
      My ComputerSystem Spec

  4. spapakons's Avatar
    Posts : 2,486
    Windows 10 Pro 64-bit 1803 (April 2018 build 17134.345)
       21 Nov 2015 #4

    For dual mode to work, you must use two separate outputs, like a DVI and a VGA. Using a Y cable on a single output, you simply split the signal on two monitors, but you see the same picture. This is used with projectors so you can see the picture on the projector, as well as another screen. What outputs your graphics card provides? HDMI can be converted to DVD and vice versa with a simple adaptor. DVI-I (including the analog pins) can be converted to analog VGA with an adaptor. HDMI can be converted to VGA or vice versa with a converter (more expensive than a simple adaptor as it has to convert from digital to analog and vice versa). As long as you have at least two SEPARATE outputs, you can have two separate pictures in dual mode. To get more you need to install a second graphics card. For motherboards with a single PCI-E 16x slot, you can install a legacy PCI VGA card (don't expect big performance, but it works).
      My ComputerSystem Spec

  5.    21 Nov 2015 #5

    Thank you spapakon. My card has a Mini-Displayport and a DVI port. So I need an adaptor Mini Displayport -> DVI adaptor, as my monitors don't have a Displayport. Thank you for your help!
      My ComputerSystem Spec

  6. spapakons's Avatar
    Posts : 2,486
    Windows 10 Pro 64-bit 1803 (April 2018 build 17134.345)
       21 Nov 2015 #6

    You are welcome!
      My ComputerSystem Spec

  7.    21 Nov 2015 #7

    The DMS59 port on your old computer was specifically designed for dual monitors though a single port. DVI on the other hand was not, Dual-Link DVI does not mean it supports multiple monitors, it means it supports higher resolution displays. The only modern port that supports multiple monitors though a single port is DisplayPort.

    To further add, while the DVI port has separate pins for analog adapters, the interface repurpose the other digital pins for analog output when a proper analog adapter is used.
      My ComputerSystem Spec

  8.    21 Nov 2015 #8

    Thank you for explaining, logicearth!
      My ComputerSystem Spec


Related Threads
Dual Monitor Alignment in Graphic Cards
Hey guys, I just downloaded Windows 10 today after a mishap with my old SSD. I have to say I'm enjoying the experience. That being said, and as much as I hate asking for information, I'd like to know if there is a way to perfectly align monitors...
I have been using HDMI cable from laptop to tv without problem. However, since updating to Windows 10 whenever I use HDMI cable, after disconnecting my laptop screen is black, it is as though it does not recognize it's own monitor. I have had to...
Solved Dual monitor problem in Windows Updates and Activation
Hi, I have a laptop now running Windows 10 and a second 24" Dell monitor. Since the Win10 update I have not been able to drag anything to my second monitor. The cursor moves to both monitors but everything opens only on the main screen. I checked...
Dual Monitor issue in General Support
I had Windows 7 with dual monitors. I never had any issue with them. I had bought a video card to make the 2nd monitor work. I recently upgraded to WIndows 10. Dual monitors still work, But if i move anything to teh second monitor,...
Dual Monitor Problem in Drivers and Hardware
Overall I'm delighted with Windows 10 but I have one relatively minor problem with my dual monitors. The taskbar on the second monitor won't auto-hide. It just sits there. Any suggestions?
Our Sites
Site Links
About Us
Windows 10 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 10" and related materials are trademarks of Microsoft Corp.

Designer Media Ltd
All times are GMT -5. The time now is 16:28.
Find Us