I have, in my build, 16gb ddr3 @1064MHz (7-7-7-20). But, they're different brands and different speeds. One is corsair vengeance 8gb 1600mhz, and the other g.skill ripjaws 8gb 1066mhz. The thing is, my useful gaming motherboard clocked them both to 1064mhz. Will this still cause problems? Because I know that when you have 2 different ram speeds they tend to cause problems, so because they are clocked the same, are they they fine?
Your motherboard automatically clocked the chips to the slowest common denominator so they could work together. If it's working fine now, you shouldn't be any problems, it did what it was supposed to do. Just note, that slower ram is bottlenecking that faster 1600Mhz ram at this point, 1064 is pretty far behind nowadays in terms of speed.