Samsung 980 Pro 500GB Gen4 M.2 SSD

Samsung's 980 Pro line of solid-state drives is their fourth generation of retail M.2 form factor SSDs, and the first to support PCI-Express 4.0. That new interface version allows for greatly increased maximum transfer speeds, potentially as much as double that of previous generations. This specific 500GB model has sequential read speeds of up to 6.9GB/s with write speeds up to 5GB/s.

Please note that many CPUs and platforms do not support PCI-E 4.0 yet, and on some motherboards the M.2 slots may not have the full PCIe x4 lanes this SSD is capable of utilizing. In either of those cases, performance will be limited by the speed of the slot. These drives can also get hot during extended read / write operations - moving data in the hundreds of gigabytes range. That is an extreme scenario, and most users will never run into it, but if the drive does get too hot it will throttle down to prevent overheating. That will reduce drive speeds until it cools off, but even in that situation performance is still well above what SATA-based SSDs offer.