What was once a part of your system that you only cared about pure storage of, has rapidly become something of vital importance.The difference between 4GB and 8GB is much less than the difference between a 2000MHz or greater kit, and one that's still down in the 1600, or even worse 1333, MHz bracket.Similarly to how DirectX solved a swathe of compatibility issues between varying hardware types, so the XMP profiles forced manufacturers to focus their energies upon creating consistent timings and fairly universal specifications. By and large memory now comes at 9-9-9-27, with only the expensive or slow models giving tighter timings, and the anything worse than 9-9-9-27 giving pause for thought.This does lead to the inevitible question of; "How different can one memory kit be from another?". After all, a dual channel kit is exactly that, surely?Today, thanks to the Kingston Genesis 2133MHz Hyper-X X2 Grey Series we shall find out if there is a need to buy new memory for your LGA1155 board, or if your old P55-based kit will still cut the mustard.