Intel's new SandyBridge-E can reach close to 5ghz on air
 

Small extract out of the news post from TechPowerup website :

"As Intel's Core i7 "Sandy Bridge-E" processors in the LGA2011 package inch closer to their mid-November launch, there is already hectic activity among manufacturers of related components such as motherboards, memory, and coolers. By now, a large section of the industry has engineering samples to help design and test their components. OCWorkbench was witness to one such pre-release setup on which a Core i7 "Sandy Bridge-E" (unknown model, could even be quad-core for all we know), overclocked to 4.92 GHz with a "regular" air-cooler. The chip was idling at 45°C. "

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