Two graphics cards ?

[thetang]

Hello
I have a PC with 2 graphics cards: ati radeon hd5850 (not supported on Mac) and a nvidia 7300GT graphics card (supported by mac)

I can connect my 2 cards under windows, and I selected the most potent (radeon 5850), it works. But mac, my ati card fan spins its 100% and a lot of noise!
Is it possible to make "inactive" my ati card mac?
Is there another solution?

thank you

 

[ludiol]

Hi there

Here is how I managed to get my OSX working with two cards inserted in my PC.

This supposes that you can select the startup PCI-E port in Bios. My Gigabyte lets me choose between PCI, PEG1 and PEG2, whereas PCI = AutoPCI, PEG1 is my PCI-E 16x slot and PEG2 is my PCI-E 4x slot

In my PEG1 slot i have a HIS RADEON HD5850 and in my PEG2 slot I have a Sapphire Radeon X1900XT 512mb.

In OSX 10.6.3 the OSX friendly card (x1900 in my case) has to be enabled by EfiString and in apple.bootlist the GraphicsEnabler has to be set to NO (Don't forget to repair permissions). This makes the HD5850 fan run on a much lower speed.

In Windows 7 the old card has to be disabled in the system and eventually the drivers have to be reinstalled.

Whenever I want to switch from W7 to OSX I first change my settings in BIOS (from PEG1 to PEG2 and select the correct HD) and then save and reboot. The same when I want to switch from OSX to W7 I change my settings from PEG2 to PEG1 and select the correct HD, save and reboot.

My X1900 is running in QE/CI 1920x1080 but I still haven't managed to get Dualscreen.