With those settings only bottlenecks are CPU and RAM.
Tested that with 2131 RAM bottleneck there is completely gone. Didn't test anything between this and 1600.
Without RAM bottleneck average gain is 5 FPS.
With 2131 RAM CPU bottleneck kicks in and 1963.5 CPU is not enough to get locked 60.
I won't provide here method how to get higher clocks and don't ask it. If author of those patches would like to share it, he will do it.