This recently started happening... I would load into an airport such as IAH shown in the screenshot and my textures would go black. Some terminals and buildings and my entire plane. I would wait 30 seconds, building textures would come back but half of the plane would still be black along with the airport. To fix this i'd go into the display settings and change the textures from high to medium then back to high, that for whatever reason works for me. After a little bit i'd setup the GSX experience get all the boarding done ext. at a nice 30-45fps. After a little bit my fps would just suddenly drop to 15 fps and will not go over 15. I tried repairing the sim, tried to generate a new P3D.cfg. My specs are GTX1660, Ryzen 7 3700X, 16gb ram, the game is on a 1tb hdd, my OS is on a 500gb SSD.