2 Different Ram In 1 laptop

aminhitman0212

Prominent
Dec 9, 2017
9
0
510
Hi i have a z500 lenovo core i7

Now i just upgrade my ram from 2GB+4GB to 8GB+4GB the question is my 4GB has 1600mhz and CL11 1.5V and my 8GB has 1333mhz and CL9 1.35V ! Is there any problem or something ? Is this cause lowing speed ?