Crucial 4GB (1x4GB) PC4-17000 2133MHz, CL15, Unbuffered, NON-ECC, 1.2V, DDR4 SODIMM. Since the introduction of DDR3 memory technology in 2007, processors have doubled in capability, SSDs have revolutionised throughput, and graphics cards have drastically increased frame rates, leaving memory as a limiting factor. With Crucial DDR4 SODIMMs, crush the DDR3 memory bottleneck and unlock a new standard of performance. Backed by a Crucial Lifetime warranty.