OK, you all got me curious about how the RAM would run if I swapped the RAM between machines, so here is the result. Both sets are GSkill Sniper, the one from the AMD is 1866 1.5V, the Intel's RAM is 2133 1.65V.
The RAM speeds, according to memtest was unchanged even though for the switch I ran both sets at 1600 even tightening timings for the AMD rig.
Apparently the RAM frequency has little or no effect on how fast it runs in the machine. It does show a large difference with winsat mem though.
The AMD system ran about 15,100 both times but the Intel dropped from 28,500 to 22,100 with the 1866 RAM.
Here are the memtest pics, the top ones are after the switch, the lowers are the same as in the OP.
(Rt click,open in new tab/window, click again to see full size)