Memory modules and CPU coolers don't always get along. Sometimes the cooler hangs over the memory slot on your motherboard so you can't fit the memory in the first and third slots, forcing you into the second and fourth; if your motherboard supports that configuration. Sometimes the cooler and the RAM modules are so gigantic they barely fit together in a system in any configuration. The chief culprit is usually an indulgently large heat spreader atop each stick of RAM.



Link: Techradar