Your GPU is the problem sir. How much VRAM do you have roughly? The 777 i would say to have at least 2g of vram but I would recommend 4g vram. Also the power of your card is very low for x-plane , i would recomend at least a gtx 760 (my opinion) for x-plane. Thirdly , the clcok speed of your cpu is low. If you could post your full specs (power supply and voltage included , I could guide you on how to overclcok safely, but it will be at your own risk as overclcoking can be dangerous if you overclcok too much. There is also most likely a bottleneck between your CPU and GPU. IE, you CPU is too powerful for your GPU, and the GPU struggles to keep up with the CPU. Regards, Rydent