Question: does all ddr3 ram fit?
Answer: You can install any 1333 or 1600 MHz stic of RAM as long as it runs at the voltage that the motherboard supports... for example, most motherboards support 1.5 volt RAM modules, some support 1.65 Volt RAM, and some support 1.35 volt RAM... but if the motherboard BIOS has the options to adjust the voltage to the RAM ...