datapath do that it 4output works on 50Hz or 60Hz multiply to input 4k@25Hz or 4k@30Hz. Nad of corse I switch on catalyst software playback from 25fps to 30fps and back.
My old one cat is: 2*4core xeon 12Gb ram GTX285 with 1 GB vram SSD 128Gb and HDD 1Tb. How crushes or whatever depends from output refresh rates and resolution? Or you trying to say me that D700 cannot handle 4k+2,5K resolution?
I had experience with same refresh rate at second output (if you means that 2 output must be at same refresh rate): its only affect on a new mac pro (on old one same load stable at any combination of refresh rate):
monitor datapath in load
2.5k@60 4k@30 8-50% (various)
2.5k@60 4k@25 10-30-60-90~100% (spasmodically)
2.5k@60 fHD@50 10-40% (various)
2.5k@60 fHD@60 8-40% (various)
fHD@50 4k@25 3-5%
fHD@60 4k@30 3-5%
So GTX285 better work than D700 , and this problem only appear on cat software (and no drop frame, all video playback at 25fps and 30fps stably) strange effect. Now I going to try datapath in 30Hz out 50Hz :/