Putting two different cards in one PC...

[leondas]

I try to take the power from the 750w power amplifier but then the mobo a ga-p55a-ud6(c) start's to sound an alarm.(I don't know how to make it stop)<----- I thought this solution as a test cause I was planning to connect an external switch to shut the power off for the 5850 when I was in os x.(there is no option in bios to disable one of the two video cards)
I m trying to find a solution.Any help will be acceptable.

Did you try unplugging the 5850 when the computer was turned off? I did that frequently when I was trying to set up two 260's and I didn't get any beeps etc.

My mobo was off when I took the power plugs out from the 5850.
I left only the 9500 which doesn't need extra power and gets it from the mobo slot.
Then when I try to boot and at the begging of p.o.s.t. process the alarm starts to sound (some error sound --- it was a continuously one).I guess it is a feature of my mobo to alert you that there is no current on the card.

 

[ludiol]

Here is how I solved my similar problem: My Gigabyte GA-P55 UD3 gives me the possbility to change the main PCI-E Slot (PEG1, PEG2 or AutoPCI)

In the first slot I have my HD5850 (in PCI-E 16x)
In the second slot I have an old XT1900.

In OSX the XT1900 has to be enabled with EFI String and in apple.bootlist the GraphicEnabler is set to NO. (don't forget to repair the permissions)
This makes the HD5850 to switch in a much lower fan speed.

In W7 you have to disable the XT1900 card in System and reinstall eventually the drivers.

Right now when I choose to change from W7 to OSX I startup the PC in the BIOS and choose PEG2 and second Harddisk (my OSX DISC) and F10 Save and Reboot

When I change from OSX to W7. I change in BIOS to PEG1 an first HD (W7) and reboot.

Actually XT1900 works with QE/CI but not Dualscreen

Thats it.

But I don't know if this works with Nvidia

 

[leondas]

Here is how I solved my similar problem: My Gigabyte GA-P55 UD3 gives me the possbility to change the main PCI-E Slot (PEG1, PEG2 or AutoPCI)

In the first slot I have my HD5850 (in PCI-E 16x)
In the second slot I have an old XT1900.

In OSX the XT1900 has to be enabled with EFI String and in apple.bootlist the GraphicEnabler is set to NO. (don't forget to repair the permissions)
This makes the HD5850 to switch in a much lower fan speed.

In W7 you have to disable the XT1900 card in System and reinstall eventually the drivers.

Right now when I choose to change from W7 to OSX I startup the PC in the BIOS and choose PEG2 and second Harddisk (my OSX DISC) and F10 Save and Reboot

When I change from OSX to W7. I change in BIOS to PEG1 an first HD (W7) and reboot.

Actually XT1900 works with QE/CI but not Dualscreen

Thats it.

But I don't know if this works with Nvidia

All the other I can do exactly as you say (and it's working that way!) but how do you enable a graphic card with EFI string?

 

[ludiol]

Search the forum and use Efi_Studio (google), this helped me a lot

 

[leondas]

Search the forum and use Efi_Studio (google), this helped me a lot

after many tries I couldn't manage to enable my nvidia via efi string.I run efi_studio but there's no 9500 plist there.(I google but i didn't find any file (plist) to download and apply on the net).I also try OSX86tools but nothing.
Finally I manage to enable 9500 via multibeast by installing nvenabler to my extra folder.
So now everything is ok as far as it concern graphics and ati 5850 seems to be disabled -- no fan spining at 100%(except that I don't have mirror screen ----> my primary screen turn to blue if there's any solution will be welcome)

BUT the problem is my sound is gone.Before I was using (and it was working VoodooHDA 0.2.56 and LegacyHDA.(anyway that was in my folder e/e and s/l/e).Now nothing and in sound preferences the digital-out Changed from line-out to hdmi)
My 9500 has got hdmi-dvi and vga outpouts.
What is wrong.How I can get audio from my external speakers?