Hi everyone, I had a 3x8 gb RAM set up with a 6core - 3.33 ghz 5,1. The ram was running at 1333 mhz. The actual ram modules were 1600 mhz non ecc. I went and bought a 4th 8gb ram module today that was matched the others and put it in my machine and now the RAM is running at 1066. I've seen others on this forum have 4x8 1333 mhz ram on a single CPU machine. Anyone have any ideas?