Question Trying to set up two monitors on RX580

[AlpineKid]

I have a new AMD Radeon RX580 8GB GDDR5 PCI-E 3.0 in a NEW computer.
Also, I do not do any gaming. I just wanted a faster, up to date computer.
I have a HP Pavilion 27xi 27-inch Diagonal IPS LED Backlit Monitor (with resolution set to 1920 x 1080) & at first had it cabled via the DVI-D (Dual Link).
I have as a 2nd monitor that is an AOC 27V2H & had it cabled via HDMI.
When I went to Settings > Display, the AOC 27V2H was set as #1 & I can/could not get it to change.
Both monitors had background color & pictures. But the mouse would/will not go between the monitors.
The reason I got this card was because it should be able to use two (2) or even three (3) monitors. And I am thinking that the mouse should/would go between all monitors.
There are no instructions on how to do this.
When I had an EVGA GeForce GT 730 w/2GB in the NEW computer, the HP Pavilion 27xi & a AOC 2217V cabled via DVI-D (Dual Link), I had background color & pictures on both. I could take and open an Excel spreadsheet and it would be seen on both screens along with the mouse going between both. I could take a .txt file and put it on either monitor. I guess what I am saying is that I could use the two (2) monitors as one (1) big monitor.
Why can I not do this with the AMD Radeon RX580 8GB GDDR5 PCI-E 3.0???
How can I get the two (2) monitors to become one (1) big monitor using this card??

When I have the EVGA GeForce GT 730 w/2GB in the NEW computer, the HP Pavilion 27xi is cabled via DVI-D (Dual Link) & the AOC 27V2H is cabled via HDMI, at monitor, & HDMI to DVI-D (Dual Link) adaptor at GeForce GT 730. Going to Settings>Display>Identify, the 1 monitor is on the left which is the AOC 27V2H & the 2 monitor is on the right, the HP Pavilion 27xi. I have color background and pictures on both monitors. And the mouse will not go to the other monitor.

I then click on the “Detect” button & I get “Didn’t detect another display.” in red. But yet there is background color and picture & the picture changes like it is supposed to.

With the EVGA GeForce GT 730 w/2GB still in the NEW computer, I went back to the HP Pavilion 27xi, cabled via the HDMI @ the monitor & HDMI to DVI-D (Dual Link) adaptor at GeForce GT 730. Then I have an AOC 2217V cabled via DVI-D (Dual Link). Going to Settings>Display>Identify, the 1 monitor is on the left which is the HP Pavilion 27xi & the 2 monitor is on the right, the AOC 2217V. I have color background and pictures on both monitors. And the mouse will go to the other monitor. A Word document or an Excel spreadsheet will span the two (2) monitors.

In this configuration, when I click on the “Detect” button & I still get “Didn’t detect another display.” in red.

 

[k1114]

You have picture so detection isn't the issue and it should already be showing both. Make sure the monitors are positioned correctly in display settings. You can click and drag to move them. You might have had the left monitor, be on the right in settings.

The rx 580 supports at least 4 monitors and depending on the version, could be up to 6.