Replacing MB and CPU, keeping 2xGPU

[SMCBuki]

Hi all,
First of all...
Merry Christmas!

I want to replace my motherboard, CPU and RAM, but I want to keep my 2 x ATI HD5770 (Gigabyte "Batman" cooler model).
Config should look like this:
i7-6700k (instead Q9550)
Gigabyte GA-Z170-GAMING K3-EU (instead GA-EP45-UD3LR)
16GB DDR4 (instead 8GB DDR2)
1st GV-R577UD-1GD
2nd GV-R577UD-1GD
...and some HDDs and SSDs.

I want to do 4k editing in FCPX and I'm wondering...
Can I use Intel HD 530 to connect to a 4k monitor and use 2x5770 as OpenCL render "slaves"? (since hd5770s are not 4k cards)
Is this configuration possible? Is it optimal? ...or is it plain wrong?

 

[Fl0r!an]

The 5770's should work fine in FCPX, but I don't think you'll be able to use the 5770's for rendering while using the iGPU for display. FCPX will most likely choose the iGPU for rendering as well-

 

[SMCBuki]

The 5770's should work fine in FCPX, but I don't think you'll be able to use the 5770's for rendering while using the iGPU for display. FCPX will most likely choose the iGPU for rendering as well-

I thought OpenCL uses all available resources for calculations, on OSX. Am I wrong or FCPX does not entirely utilize OpenCL?

 

[Fl0r!an]

It's up to the application to decide which OpenCL resources it'll use. FCPX will use multiple GPUs, but I don't think it'll mix & match different models.