AOC Monitor flickering with MacBook Pro

For Christmas I received a 20in LED Monitor to use with my MacBook Pro. Here are the specs i think you all would need of the Monitor and Mac Book Pro:

MacBook

Mid 2012

Intel Core i7

16GB RAM

NVIDIA GeForce GT 650M 1024 MB

Monitor

20 inch LED

AOC e2070Swn

I am using a HDE mini display port to VGA. It flickers every few seconds. I have tried every resolution that the MAC is given me to no prevail. I changed the contrast and brightness. I have also tried using the Monitor on a Windows PC. It works with on issues on a Windows PC. It has no other connections only a VGA port. Do anyone know what I can do to stop the flickering of this monitor with my MacBook Pro? If you all need any more information please ask. Thanks in advance for helping out.