Hyperx hx421c14fbk28 is a kit of two 512m x 64 bit 4gb ddr4 2133 cl14 sdram synchronous dram 1rx8 memory module based on eight 512m x 8 bit fbga components per module each module kit supports intel extreme memory profiles intel xmp 20 total kit capacity is 8gb each module has been tested to run at ddr4 2133 at a low latency timing of 14 14 14 at 12v power supply vdd 12v typical vddq 12v typical vpp 25v typical vddspd 22v to 36v nominal and dynamic on