I resently added a 3rd monitor to my setup. Before that I was able to run the PMDG 737 with VC on 2 windows 1920x1080 with reasonably framerates on most major airports.
Now when I open a 3rd VC window on the 3rd monitor (1920x1080) framerates drops to 2-3 pfs.
I'm able to run some other AC, like the Level-D with 3 VC windows open, and FSX running relativly smooth..
I'm running FSX on an i7-2700K (@ 4,5), 2x8Gb Kingston HyperX Ram, Gigabyte HD 7970 3Gb (@1100), Win7 x64. Both OS drive and FSX drive is SSD's.
Anyone who can see the bottleneck causing this "problem"?
Is it the PMDG's on 3 windows that's too heavy on the CPU?
Or is it a GPU-problem, and if it is - is the solution a card with more Ram or "just" more power?