fps/in game skipping issue potentally game breaking

so today iv been grinding ranked (which if im honest im pissed right off about how littile my ip gains/losses make no sense) when last game i had massive framerate issues.

i was avarageing less then 40fps when normally i avarage arround 140fps and getting massive "skips" in game. what i mean by "skips" is that the game would freeze for about two seconds at a time go to a stupidly low framerate(4-15) for about another two seconds uppon almost anything happening. i found the skipping happened when: a lee sin Q was used (only first press),** jayce ult and hammer E**,** diana ult**, veigar ult, lucian Q, lux ult and W,** sion Q that was not fully charaged** also** sions passive activeing and his passive dieing** , nami ult.

i double checked to see if this was happenening on any other games and leauge was the only game this issue is effecting.

i have not played any more games of leauge to test if this was a one time thing due to various fustrations surrounding caused by leauge.