What does memory standard actually mean? Is it the optimum memory clock speed or the max the board can support? For example, if the memory standard of a board is DDR2 1333 OC, will 1066 memory not be an optimal choice?
More aboutmemory standard
It's what the board is guaranteed/rated to run at. No more, no less. Going faster means you have to Overclock and may run into stability and heat issues. Slower = Underclock: