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!
What makes you think the content is different on the Analog vs Digital lines of a single socket?
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
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).
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!
You are welcome!
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.
Thank you for explaining, logicearth!
