On the box the ASUS ROG Poseidon GTX 980 Platinum states a base of 1178MHz and a boost clock of 1279MHz but in testing [H]ard|OCP saw the card sitting at 1328MHz in game while on air cooling.  They then proceeded to hook up a Koolance Exos-2 V2 and pushed the card to 1580MHz in game, though the RAM would only increase by 1.1GHz to 8.1GHz.  As you would expect this had a noticeable impact on the performance and while it might not compete with the just announced Titan X at $640 it is also far less expensive though still $200 more than the Sapphire Vapor-X 290X it was tested against and $90 more than the 8GB version of that card.  If you have the budget this GTX 980 is the fastest single GPU card on the planet right now.

"The highest overclocked GeForce GTX 980 based video card just landed. If the ASUS ROG Poseidon GTX 980 Platinum video card with a hybrid air and liquid cooling system doesn't impress you, we are not sure what will when it comes to GPU. We push the Poseidon clocks and pit it against the AMD Radeon R9 290X for an ultimate showdown."

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