I'm just letting you guys know so ppl stop whining in here that Claymore is somehow intentionally gimping the RX cards. The fact that you quote AMD marketing stuff about color compression just shows that you are grasping at straws and wishing upon stars. Any speedup by these tweaks is only for changes in pixel colors in gaming scenarios, not compute tasks. You have to look at the "uncompressible data" part of the graph and you see that RX 480 gets no speedup due to delta color compression algos. Same thing goes for tesselation and AA optimizations in the compute units.

You also can't draw conclusions by underclocking the memory unless you use the same memory straps for every frequency...otherwise, every 125 or 250MHz drop the timings tighten, so a lot of the loss in bandwidth is made up in lower latency.