Question lenovo y50-70 vertical lines pink and greeen after overclocking laptopemoniter refrash

Oct 6, 2019
my laptope screen is 4k and standerd refrash rate is 64 htz but when i overclock 48 htz to 60 then pink verticle lines appared plx gauid me how to change my refrash rate 48 t0 60 without any problem...and one thing my laptope disply are locked in to 48 htz .....and i using for overcloacking custom resalution utillity....thanksss