1. PCIe Gen4 storage technology requires a compatible motherboard. WD_BLACK SN850X is backwards-compatible with PCIe Gen3. 2. Based on read speed. 1 MB/s = 1 million bytes per second. Based on internal testing; performance may vary depending upon host device, usage conditions, drive capacity, and other factors. 3. 1GB = 1 billion bytes and 1TB = 1 trillion bytes. Actual user capacity may be less depending on operating environment. Western Digital, the Western Digital logo, WD_BLACK, and the WD_BLACK logo are registered marks or marks of Western Digital Corporation or its affiliates in the U.S. and/or other countries. NVMe is a mark of NVM Express, Inc. PCIe is a mark of PCI-SIG in the United States and/or other countries. Windows is a mark of Microsoft Corporation. All other marks are the property of their respective owners. Product specifications subject to change without notice. Pictures shown may vary from actual products.