Geekbench in OSX 10.0.1
http://browser.primatelabs.com/geekbench3/1509989 (This is @ 4.3ghz)
The Unibeast settings are in the video. You have to copy over the patched kernel AFTER installing OS X.
In multibeast, I believe I used...
-TRIM Patch
-VooDooTSCSync 6 Cores (included in video I linked)
-NullCPUPowerManagement
-RealTekRTL81xx
Of course, you'll need NVIDIA web drivers for 9xx cards. Install the web drivers in safe mode with graphics acceleration disabled (of course.) Really laggy.
That's all I remember ever installing. Don't install Intel generic AHCI SATA, IOACHIBlockstorageinjector, or USB 3.0 kext. They would cause the system not to boot. My USB 3.0 ports work fine without it.
Was rendering videos in Adobe Premire, the system flew through everything with graphics acceleration.
1. No, I think it works out of the box
http://www.tonymacx86.com/desktop-compatibility/102506-nvidia-geforce-gtx-760-works.html
2. I installed OS X with all my SSDs plugged in, and Windows 8.1 installed, perfectly fine.
3. Yes, of course. Plug them in the same GPU.
No issues or complaints with this board after BIOS update. X99 is a new platform, so issues were expected, and they were ironed out accordingly.
Sorry, I don't know how to help you
Try the "-f" startup parameter, that fixed a lot of issues for me.
You could try clover boot loader, not sure. I stick with chameleon because it's what I know and it works.
Have not heard of this issue. Are both GPUs recognized in OS X?