Power saving mode

Riot ever since you updated the client i've heard reports from my friends that their computers entering power saving mode for no reason an it only happens while playing league, it happened to me once while play 3v3 but not during ranked 5s so i didn't think anything of it. Today it happened during a ranked game after restarting my computer i tried entering a 5s map style custom game an it happened agion. No one i know of has found anyway to fix this problem so they all just stopped playing an i don't wanna do that i enjoy league