The newest, fastest standard for M.2 SSDs, PCIe 5.0, has been around for a couple of years, but only this year brought a consumer release for the fastest M.2 SSDs. The first crop of M.2 NVMe SSDs using this standard promise speeds of 10,000MB/s or higher. When the second wave comes, expect speeds of 16,000MB/s, close to the theoretical limits of the PCIe 5.0 specification.