Thanks for your great guide. It helped me recover from trying to install 10.13!
Anyhow, what BIOS settings are you using to get 4.2GHz? Mine is stuck at 3.2GHz no matter what I do or else it's a kernel panic.
I have 2 280X running 2 monitors. I'm pretty sure it can handle 3. I had to install the bootloader to an EFI partition though: http://www.tonymacx86.com/general-help/115818-install-bootloader-extra-efi-partition.html
You should hook your friend up with your 650ti and get yourself a 280X. I just replaced my two 650ti's with a 280X yesterday. Amazon had manufacturer refurb MSI 280X's for $259 the other day. My BruceX score with a single 280X was 34 seconds compared to 48 seconds I was getting with two 650ti's...
Here's a link to a benchmark many are using that will help in deciding what graphic card to buy for FCPX use:
(When you run the benchmark, just output to standard ProRes. Most are having trouble exporting to...
I added a 2nd identical MSI 650ti and it made a significant improvement in FCPX. I used this 'benchmark':
My result went from 76 seconds to 48 seconds by just simply dropping the card in - no configuration...
It's been working great with FCPX 10.1. I didn't have to do anything special. It's the same chip on both cards so I'm not sure why yours wouldn't work. I'm using mine on a Gigabyte motherboard. I'm thinking of adding a 2nd video card to see if there's any additional performance gain with 10.1.