3rd monitor on Radeon HD7800 series

BdeBrouwer

Honorable
Jan 24, 2014
2
0
10,510
Alright, tried searching the forums but I can't really figure out the go to solution. My apologies if this has been answered before, but I couldn't make out the right solution out of all mentioned solutions.

The PC i'm using was build by a company and it has the GPU Radeon HD7800 series - don't know the specific type, but I've got 2 DVI and one HDMI connection.

Because I already had to monitors, I've got one of the connected via DVI number one and the other one through HDMI. They both work smoothly.

Today I got my pentablet in, which functions as a screen as well and I opted to connect this through the second DVI port, which is located underneath the first.

When my PC is running, I have nothing is shown my my tablet.
When I boot my PC, the windows logo is shown on the tablet and the monitor on my first DVI remains blank (No video input detected it says) but all switches back when I need to log in.
When I switch both DVI cables, the problem remains the same with the monitors behaving as the other would (the problem still remains, but indicates nothing in the cabling nor devices is wrong.)

When I open up the Windows settings I can't duplicate the monitor of DVI one (which is what I want to go for) nor extend the desktop over all monitors - on the screen that doesn't display stuff, windows doesn't except any other setting then "disconnect this display".

I have got the lastest driver and Catalyst control center installed.
Running on Windows 8.1 Pro 64-bit.

As I'm not too handy with PCs outside my design software and I'm not English I would appreciate it if someone could take time to explain to me easily and step by step on how I can fix this issue.

Cheers,
Bart.
 

BdeBrouwer

Honorable
Jan 24, 2014
2
0
10,510
So this active adapter is just a thing I buy and place between the monitor cable and my graphics card, right? Just to get the 3 monitors working, even when I want number 3 to be a clone of number 1?

If I'm going to need one no matter what, I'll pick one up tomorrow.