For those who's cases are small and CPU sockets are crowded the enormous dual fan 1kg heatsinks you commonly see are not an option.  BeQuiet has a smaller cooler called the Shadow Rock Slim which is a much better choice.  As the name implies it is quite slim and so should not interfere with your RAM's heatspreaders and the 159mm (6.25") height means it can fit in a wide range of cases.  Even with it's small size the tests that FrostyTech performed show it performs quite well at stock fan speeds, though they do not recommend running it a lower speeds on hot processors as the performance simply changes too much.

"BeQuiet's Shadow Rock Slim heatsink stands 159mm tall and has a footprint of 130x74mm so it will fit most motherboards where space between the memory slots and videocard is on the tight side. The Shadow Rock Slim heatsink weighs 730 grams and is constructed around four 6mm diameter copper heatpipes onto which are swaged raw aluminum cooling fins."

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CASES & COOLING