Out of the box the ASUS STRIX R9 380X OC has a top GPU speed of 1030MHz and memory at 5.7GHz, enough to outperform a stock GTX 960 4GB at 1440p but not enough to provide satisfactory performance at that resolution.  After spending some time with the card, [H]ard|OCP determined that the best overclock they could coax out of this particular GPU was 1175MHz and 6.5GHz, so they set about testing the performance at 1440p again.  To make it fair they also overclocked their STRIX GTX 960 OC 4GB to 1527MHz and 8GHz.  Read the full review for the detailed results, you will see that overclocking your 380X does really increase the value you get for your money.

"We take the new ASUS STRIX R9 380X DirectCU II OC based on AMD's new Radeon R9 380X GPU and overclock this video card to its highest potential. We'll compare performance in six games, including Fallout 4, to a highly overclocked ASUS GeForce GTX 960 4GB video card and find out who dominates 1440p gaming."

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