Game has been tested at the release. After hours of gameplay it creeps up to 11-12gb depending on the scene and this is without RT. Nobody tests for few hours they all do short benchmarks runs. I dont recommend 12gb gpus if you gonna use RT/PT. I expect performance degradation overtime as you run out of vram. You can do optimized settings on such cards to reduce the usage but whats the point then. This is the update 12 and vram usage is slowly going up with every update i noticed. After Cynthia boss battle was over before chapter ended i had 13gb vram usage in the most demanding forest area. Then Bright Falls with 11gb and in next chapter with Wake usage dropped to 9.2gb.