Unhappy [Q] Some troubles after flashing cocore8.8/9.0 n OC

i pushed the max clock rate to 1.1ghz,it's unstable and rebooted again n again

i knew i have to stop it,so i just set it into original rate,then i flash oem rom

the result is my phone just always keep in max clock tare@1ghz although the governor setting is ondemand

i can't phone for a long time,it will stop conversation suddenly,duration usually not more than a minute

then i flash cocore 8.8 again, i set max rate @400mhz,but still can't phone normally,it just stop stop stopstop

bad english

PLEASE HELP ME