Dual screen mirrors, won't extend

[Some-1]

Hello,

I'm running a hackintosh with a:

• CPU: Intel Core i5 6400 Skylake with integrated HD530 graphics
• MOBO: Gigabyte Z170MX-Gaming 5

I've installed OSX El Capitan and it seems that all is working fine. Now I've connected a second screen. But this screen is a mirror of the first one. I can't get it a an extended screen. When I click on 'about this Mac', it only shows me one connected screen.

One screen is connected by HDMI, the other one by DVI. Both are the same Dell U2312H

Since both screens are working, I hope it's just a setting to get the screens extended instead of mirrored. Does anyone know how to fix this?

 

[BreBo]

Since both screens are working, I hope it's just a setting to get the screens extended instead of mirrored. Does anyone know how to fix this?

Go to System Preferences -> Displays -> Arrangement and uncheck Mirror Displays

 

[Some-1]

Go to System Preferences -> Displays -> Arrangement and uncheck Mirror Displays

Unfortunately, that is not the solution. It also sees just one screen, see below:

The screens are also not recognized correctly. They or 23" Dell U2312H.

When the system boots, both screens are directly mirrored.

 

[Fl0r!an]

There are various threads on enabling dual displays on Skylake HD graphics. It's not straightforward and usually requires kext patches and workaround procedures (e.g. hotplugging one of the screens).

 

[aol]

I get extended desktop to two monitors as long as I turn on the second monitor after POST (i actually turn it on when the login screen displays). This procedure works 80% of the time. It's flaky as hell, but it does work. I followed the 10.11.4 post on 530 on Skylake to add the 4 port patch, enable Intel, and add ig-platform-id to 0x19120000; I followed another thread to manually determine which ports are which connectors and added the right patches so that connectors 0x05 and 0x06 (the two I use) are the correct port (HDMI and DVI; the default is DP); since I use SMBIOS MacPro 6,1 I applied the AGDPFix to fix the second monitor not coming on at all; and I manually determined through trial and error the best boot sequence (which monitor to have on at boot, and how to turn on the second monitor; some folks have to hot plug, some have to turn on). And make sure you have pre-allocated at least 64MB of VRAM in the BIOS. That's all under el cap. If you're on sierra, you probably have to ALSO add the glitch fixes for the glitch in the upper left corner.

 

[kecinzer]

I have same problem with HP Ultraslim dock. I have here 2 display ports and connected 2 HP E233 displays. When both displays are connect into DP ports it acts like one external monitor. In settings I can see only one display. When I one of them connect with VGA cable, I can see both of it. But VGA connection is weird and I would like to make it work over DP cable.