Solution: Gigabyte Radeon 6670 with Dual Monitors on Mountain Lion

[keykiller]

I've found a way to have dual monitors (HDMI + DVI) in Mountain Lion using a Gigabyte Radeon 6670.

First of all, I followed the installation procedures in here:
http://www.tonymacx86.com/mountain-...mountain-lion-6xxx-gpu-issues-fix-inside.html

After the installation, I started Mountain Lion with GraphicsEnabler=Yes. My card was properly recognized in 'About this Mac' using the Bulrushes framebuffer personality. However, only my HDMI monitor was working. The DVI monitor was not receiving any signal.
This problem also happened in Lion when using Bulrushes (which is the best personality for this card).

To get both HDMI and DVI working in Lion, I used to set PCIRootUID=0 -- but this trick does not work in Mountain Lion.
As I understand, PCIRootUID=0 forces Lion to use the generic RadeonFramebuffer personality.
So I was looking for a way to use this generic personality in Mountain Lion.
As it turns out, it can be done by setting AtiConfig=qwerty or any value that do not correspond to a valid personality.
Both my monitors are now working fine and with QE/CI.

TIP:
You can check which personality you are currently using by running the command "ioreg | grep ATY" in the Terminal.

 

[GTHorsey]

I've tried this and cannot make it work. Can you confirm what Framebuffer your 6670 is using? If I specify AtiConfig=qwerty, I get the generic "RadeonFramebuffer". Both monitors work fine, but I get no QE/CI. "About this Mac" shows "AMD Radeon 6xxx 1024 MB".

If I don't specify any AtiConfig, it uses "Bulrushes". Full QE/CI. But my DVI port is dead.

 

[keykiller]

I've tried this and cannot make it work. Can you confirm what Framebuffer your 6670 is using? If I specify AtiConfig=qwerty, I get the generic "RadeonFramebuffer". Both monitors work fine, but I get no QE/CI. "About this Mac" shows "AMD Radeon 6xxx 1024 MB".

If I don't specify any AtiConfig, it uses "Bulrushes". Full QE/CI. But my DVI port is dead.

You shouldn't imply you don't get QE/CI just because About this Mac shows a generic card.
It shows a generic card because of generic framebuffer.

Here is how you can test whether you have QE/CI working or not:
http://legacy.tonymacx86.com/wiki/index.php/QE/CI_Graphics_Acceleration

 

[keykiller]

You may want to consider using both your HD 3000 (I see you have an i7 2600k) and your Radeon 6670.
You could connect one monitor in each of them and not worry about this workaround at all.
Besides, if you make your HD 3000 the primary card in BIOS and change your system definition to Mac mini 5,1 or iMac 12,1 or 12,2, you may even get AirPlay Mirroring to work.