I recommend moving that GPU to another slot on the motherboard, preferably the second to last slot (that PCIe x1 slot with its end cut off), and removing that bottom PCIe card (idk what that card is). Then, you should have more BCLK headroom, also set your DMI version to "Gen 1", which allows higher BCLK OC margins. Then, you should be able to tune that BCLK up a bit more, and thus, get a higher frequency! Just want to help!