Beta client

Hallo Riot Team and other players..! My problem is the new Beta Client its look nice but got a lot of problems and one of this is that make my PC a lot slower..! and i have tested i didnt open LoL client after restart my computer and all was perfect but then i opened everything was crashed plz riot Fix this..! I am trying to launch the old one but after i close it its come beta cliend again..! :/