Having already seen what the ASUS R9 280X DirectCU II TOP can do at default speeds the obvious next step, once they had time to fully explore the options, was for [H]ard|OCP to see just how far this GPU can overclock.  To make a long story short, they went from a default clock of  1070MHz up to 1230MHz and pushed the RAM to 6.6GHz from 6.4GHz though the voltage needed to be bumped from 1.2v to 1.3v.  The actual frequencies are nowhere near as important as the effect on gameplay though, to see those results you will have to click through to the full article.

"We take the new ASUS R9 280X DirectCU II TOP video card and find out how high it will overclock with GPU Tweak and voltage modification. We will compare performance to an overclocked GeForce GTX 770 and find out which card comes out on top when pushed to its overclocking limits."

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