The Sapphire HD 7970 OC Edition sports two profiles, on set to defaults and one with a mild overclock of 1GHz on the GPU and effective memory of 5.8GHz but it really is the cooler which makes this card special.  The dual fans and extensive heatsinks allow for quieter and cooler operation than the reference design which can be more important to some than a huge overclock and since it is cooler you have a better chance of getting a higher manual overclock if you are so inclined.  Overclockers Club were very impressed with the card and even more impressed by Sapphire’s decision to include an Active DisplayPort adapter.

"The Dual X cooler is really the bonus to this particular card; it is the real feature that sets it apart from not only other 7970s but also other high-end cards. Under full load it shows off its true colors as one of the best cooled cards on the market while remaining quiet (in a relative manner). With the fans at full it can dissipate quite a bit of heat away from the card to keep it cool and ready for more. It might dump a little more heat to the case at idle and run slightly "hotter" at idle, but it is much better than a constant vacuum cleaner noise coming from your case."

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