2 GPU: One for windows and one for OSX GTX980

[tipex]

Hi,

The weather is getting cold, no more barbecue and outside party. So i fell to game a little bit this next months
I would like to buy the new Geforce GTX980 but i know it's not compatible with OSX yet.
But i may have a solution. Keep my old GT640 for OSX (i don't need 3d power in my OSX usage) and get a GTX 980 only for windows.

Since my screen have 2 input i will use HDMI for osx and DVI for windows, for example..

Now the software part.. i know exactly how to disable the GT640 in windows to make it GT980 by default, but i'm wondering if there is anyway to do the same in OSX to disable the GT980 and make GT640 by default

Any idea ?

 

[Manic Harmon1c]

I was thinking of doing the same thing except with a HD 6850 and a GTX 980. In OS X the GPU can be disabled with the DSDT or SSDT. In Windows I don't know (although it sounds like you do), but I'm thinking it will probably see the other card as being connected to separate displays, so as long as your games open on the display/port that the 980 is powering it should use that card.

 

[tipex]

In windows you can simply disable a device in the configuration panel. I may buy it in few week, i gonna try it

 

[Manic Harmon1c]

I have an Nvidia 8800GT I'm testing this method with just to see if it's a viable option. I'm having trouble disabling the card through SSDT... If I disable that PCI slot, it simply detects it in IOReg as something else. I think this is the correct method to use, which I haven't tried yet. http://www.projectosx.com/forum/index.php?showtopic=889

More on the function disable register can be found in the intel PCH data sheet on page 423. http://www.intel.com/content/dam/ww...datasheets/7-series-chipset-pch-datasheet.pdf

Having the card enabled in OS X shouldn't be a big deal, except that I noticed whenever the 8800GT is connected that's what software like Cinebench sees my graphics card as even though it's in the secondary slot. However, the benchmarks don't suffer because of it, it's obviously using my 6850 still. It may become a problem though with a card such as the GTX 9xx that doesn't have qe/ci.

I was able to test disable my 6850 in Windows and only using the 8800GT, which worked fine. It's re-enabled on every boot though, which isn't exactly ideal.

I will keep testing and report back.

 

[tipex]

awesome !

I didn't have time to start my test yet but when i'll do i'll post feedback here.

 

[Manic Harmon1c]

no luck here with disabling it from ACPI tables. I've tried disabling it by using Name (_STA, Zero) as well as just deleting it from the DSDT completely. It always names itself something different under IOReg instead of listening to me. I wanted to try using the function disable register, but the one in my DSDT doesn't have any options for disabling any PCI-E slots, I only have the option of disabling root ports and a few other devices. I even tried copying the _OFF method from an nvidia optimus notebook's dsdt and using that, but I couldn't get that to work either.