I have both XP11 and P3Dv4, and both simulators provide about equal performance in frame rates.  One key difference is XP11 is always pushing my gpu (nVidia 970) temps to 80c with the fans running at high speed.  In contrast, I can fly the PMDG 737 in Orbx scenery in P3Dv4 and the fans run at a very low speed with cooler temps.  Any computer guru's here understand why XP11 is so much more demanding?  

In very basic terms, P3D/FSX is CPU dependant.  X Plane is GPU dependant.  X-Plane uses the CPU for code, flight models, etc...  Anything to do with graphics, it uses the GPU.

49 minutes ago, GoranM said:

In very basic terms, P3D/FSX is CPU dependant.  X Plane is GPU dependant.  X-Plane uses the CPU for code, flight models, etc...  Anything to do with graphics, it uses the GPU.

Good explanation, thank you for the insight.

11 hours ago, GoranM said:

In very basic terms, P3D/FSX is CPU dependant.  X Plane is GPU dependant.  X-Plane uses the CPU for code, flight models, etc...  Anything to do with graphics, it uses the GPU.

A little bit too basic maybe. X-Plane is still very much CPU bound in its current state. However it utilizes the GPU much better, mostly for features P3D doesn't even have (such PBR and other effects), thus the higher GPU load compared to P3D. Still, many things "graphics" are still calculated by the CPU, such as scenery, lights and shadows. A well tuned X-Plane installation uses both CPU and GPU equally (frametimes both around 0.030 for a consistent, locked 30 FPS), however, high-end GPU's are bored quickly unless you run at very high resolutions - especially since X-Plane 11 default weather is much easier on the GPU compared to X-Plane 10. One thing you will NEVER see in X-Plane however is a bored CPU.