Frame rate issues in the new season

lately I have noticed with the new patch that my frame rate will drop to levels which are very abnormal for me when playing. I noticed when enemy minions first walked into my vision that my frames would drop from about 100 fps to 45 fps. I feel like some of this has to do with some of the new rune changes and their interactions. It makes playing league less enjoyable to lose fights due to fps drops and I do not want to invest money into a new computer. hopefuly riot will work on the optimization of the game so that it works better for casual gamers such as myself.