First post go easy on me...

i have a GTX 960 and a GTX 780ti, i need to connect 2 monitors and a cintiq to dough's video card...
right now i have my main monitor and my cintq to the GTX 960 and my second monitor to the GTX 780ti
the performance right now is pretty bad... i am only using the 980ti to render in C4D, the speed of the render is ok but the viewport movement is just stuck... i have to pause octane update all i need and unpause again to see the effects...
is there an optimal way to connect the monitors for better performance?