RAM old and new

[pants0705]

I had 2x4gb of 2133MHz corsair vengeance ram and just bought another 2x4gb of 3000MHz corsair vengeance ram when I installed it stated that I should put the older ram closer to the processor (didnt know if this was true) but I did it anyway, my pc would boot but wouldnt give any signal to my monitors, is this because they are different MHz? Or anything I can do to make them both work together

 

[Dark Lord of Tech]

When mixing modules it's hit and miss , what are your specs?