I've been running 3x 1920x1080 monitors for over a year by now, by using 2x VGA cables coupled with 2x VGA -> DVI-I (Dual link) for my 2 legacy monitors, and then using a HDMI -> DVI cable coupled up with a DVI -> DisplayPort Active Adaptor for my 3rd monitor.
All this was working fine with my old Radeon HD 5850 GPU.
Today i upgraded to a new Sapphire Radeon 7970 GPU, which caused me some issues.
The 5850 had 2x DVI-I (Dual link) inputs, 1x HDMI and 1x DisplayPort, which was perfect
But the new 7970 only has 1x DVI-I (Dual link) input and then one DVI-D (Single link), and then HDMI and DisplayPort.
This means the adaptors i currently own can't connect all 3 screens, because there is a slight difference in the number of pins between a DVI-D and DVI-I.
I chose to break out my HDMI cable to rectify this problem and ditch using the DVI-D (Single link), simply connecting the HDMI cable directly from my screen to my computer.
This is where the problem arrises.
When i boot up, my 1st and 2nd screen are fine and i can see the picture. But the 3rd screen (the one connected by the HDMI cable) will simply not turn on.
It stays black, saying that "No signal is recieved" on the screen, but i can move programs over to that screen by dragging them with my mouse, i can start a movie on the screen and hear the sound, etc etc.
Even Catalyst Control Center can find the screen and identify it.
It just won't show a picture.
I've tried changing cables around and i've definately been able to say that all 3 monitors are fine and working.
I used the HDMI cable just last week at my friends place, so i'm 99.9% sure that works fine too.
I can use TeamViewer program (remote control) to view my screens from my tablet, and this also shows the 3rd screen, with icons on the desktop and i can see what is happening on the screen. (So the computer realises it's a screen, uses it but won't show it).
I'm hoping someone can help me, as i'm fairly stumped as to why this doesn't work...
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