So basically, we do support 11.1 features with 11_0 feature level through the DirectX 11.1 API. We do not support feature level 11_1. This is a bit confusing, due to Microsoft naming. So we do support 11.1 from a feature level for gaming related features."
AMD's Radeon HD 7000 "Southern Islands" GPU series is fully compliant with DirectX 11.1 (except the rebranded products from the 6000 family).