Jacob Bowerman :
hey, if i get a quad channel kit but my motherboard is only dual channel, if i put all 4 stick in then that means im running 2x dual channels. for any reason would that not work?
and also what if i put 2400mhz ram in a slower motherboard, say for example the motherboard only supports 1600mhz, would it just under clock it itself or would it crash etc?
and for any reason that you can see would this build not work? or any recommendations
Quad channel kits are simply a package of 4 DIMMs that have been verified to work in a quad channel configuration.
There is nothing mechanically or electrically different between a pair of dual-channel kits and a single quad-channel kit, it's purely marketing and quality assurance.
As for the rated speed. When the system firmware initializes the DRAM it first reads data from a chip in the DIMM known as the SPD, or Serial Presence Detect. Despite the fancy name this is just an EEPROM that's accessed over I2C. The SPD contains module information including the speed profiles that the manufacturer has programmed into it. The top profile will usually be that which the module is marketed at (such as DDR3-2400) along with supply voltage, timing information, and whether or not the profile is a JEDEC standard profile or an XMP overclocking profile. The firmware will compare the information in the SPD and pick the profile that best matches the capabilities of the memory controller unless configured before hand to do otherwise.
The memory will not be underclocked if it is not compatible, rather it will not be overclocked until configured to do so.