It has nothing to do with computer speed. I have a PC that is more than capable of playing league at 60+ fps. On sr, dom and old tt I have mostly 60 fps with small drops.
It's some kind of bug or something. It happens on certain areas of the map when all 6 players are there.
Specifically I have noticed that it drops during 3v3 fights at both altars and bot lane.
Fights everywhere else have so far been fine.
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