U.2 vs. M.2 vs. SATA Express Interface Comparison & Speeds | GamersNexus - Gaming PC Builds & Hardware Benchmarks
What is U.2 SSD (formerly SFF-8639)? | Definition from TechTarget
Amazon.com: PCI Expansion to U.2 Adapter Card, PCIe X16 to 4 Port U.2 NVME SFF-8643/8639 Expansion Card, High Speed PCIE Split Expansion Card with LED Indicator for Windows : Electronics
Kingston's datacenter capable (24-7) NVMe SSDs (DC 1500m) only work with mainboard that have U.2 interface – U.2 on Desktop is called mini-SAS or SFF-8643 on Servers | dwaves.de
U.2 | NVMe
M.2 Ssd To U.2 Adapter 2in1 M.2 Nvme And Sata-bus Ngff Ssd To Pci-e U.2 Sff-8639 Adapter Pcie M2 Converter For Desktop Computers - Add On Cards & Controller Panels - AliExpress