iMac RAM Issues

My system:

iMac Mid 2010 21.5 Inch

3.2 GHz i3

macOS 10.13.4

Issue:

As my mac was slowing down, I decided to replace my dual 2 gigabyte ram modules with one stick with 8 gigabytes of ram. Problems occurred after I took out the existing ram modules and replaced them with the new module. The mac boots up normal, but then starts to restart after I open up a program and leads to a screen saying the mac restarted because of a problem. For background information, I also replaced my old 1tb hard drive with a 2tb SSD with a fresh install of High Sierra.

New Ram Specs: Corsair MacMemory DDR3 1333MHz CMSA8GX3M1A1333C9

It would be appreciated if a solution could found as I can't return the 8 gigabyte stick I purchased.