HyperX HX426C15FBK4/16 is a kit of four 512M x 64-bit (4GB) DDR4-2666 CL15 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) 2.0. Total kit capacity is 16GB. Each module has been tested to run at DDR4-2666 at a low latency timing of 15-17-17 at 1.2V. Additional timing parameters are shown in the Plug-N-Play (PnP) Timing Parameters section below.