Is it safe using RAMs with different Frequencies
I'd like to use 2 x 4GB DDR3 1600 dimms in a motherboard capable of only DDR3 1066. The DDR3 1600 is on sale and the cost is identical to 1066 dimms. It'd be nice to have these faster sticks around should i upgrade the motherboard. I assume the RAM can under clock itself or be changed in the BIOS.
While obviously it's less than ideal situation, I don't know if there are other unintended consequences in terms of stability, performance and longevity of the board and said RAM. Am I doing any damage to the memory controller or RAM?
I've always bought RAM at the max speed specified for the motherboard and I've never gone over so I'm not sure if there any caveats to this at all.
Edit: I intend to use the RAM in pairs. I know that mixing RAM speeds is just a bad idea.