After a recent patch (can't tell exactly which) my game started dropping frames in big teamfights. Before it was a 60 constant even on my old graphics card (Radeon HD7770) and now it drops to 25-50. All graphical settings are maxed, eye candy is on as well as character inking, resolution 1920x1080.
-AMD Athlon x4 750k (OC-4.0GHz) CPU
-Sapphire Radeon Rx-480 8GB GPU
-8GB system ram 1372MHz
If you need any additional info just ask.