There's one thing me and Riot can without a doubt agree on.

SERIOUSLY, TRY LOW-SPEC MODE IF YOU'RE HAVING PERFORMANCE PROBLEMS.

Taken from the patch notes.

You can't believe how often I would hear people complain in skype call or in-game about the new client and how it ruins their performance but then it comes out that they didn't enable low spec mode. Especially now that they "buffed" it, it should help a ton with these issues. As someone who is a proud member of the Potato Master Race myself, I can highly recommend it to you.