Default [Q] Games lagging in Cyanogen Mod 11

Well,I have a average knowledge in flashing custom - Roms/kernels,When I tried to install CM11 through CMW 5.0.x.x,I got status 7 error,so I installed CM11 through the official App realeased,everything is fine, when it comes to games,I experience a horrible lag,games won't lag on my stock 4.1.1,What is the reason for this? and how I can i fix it?