I don't really know why but since the item update I have had to back my graphics settings all the way down to keep the game playable. I suspect it has to do with the number of effects visible in frame because it usually happens when there are multiple ults happening. I'm not too impassioned about it because I understand this game is in playable alpha so I don't expect it to be polished or optimized. It's just annoying when there's a big team fine and I basically get to wait to see how it played out.
RX580 8gb