Then what is it? I can show you countless cores from this system on various recent GPUs showing performance that is either acceptable, or not acceptable, in Port Royal, for the speeds I'm running, only thing that changes regularly is drivers.
Saying "that score is low" and not providing any further details or suggestions is just annoying & not at all helpful. That's like people telling someone to increase their CPU overclock - some people can't do that or don't have a CPU that can run any faster due to either cooling/temperatures or other reasons, mine in particular will not run any faster, I've tried 5.1 & 5.2 at pretty high voltages & nothing will make it pass even a single run of benchmarks at those speeds that I have tried. Either way it was a massive improvement going from a 3930K X79 setup I had previously to this.
While Port Royal is about 90% GPU, there is some score & headway that can be had from CPU/system RAM changes, that I know for a fact.