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If you think USB is bad, try looking at all the various things that can be connected together with M.2 slots vs. the pairs of devices that will actually work to
by eigenvector 6y ago
If you think USB is bad, try looking at all the various things that can be connected together with M.2 slots vs. the pairs of devices that will actually work together despite having the same slot. I have a degree in electrical engineering and after years I only just realized that there are actually PCIe M.2 storage devices that only support AHCI mode not NVMe.
- wtallis 6y ago> I have a degree in electrical engineering and after years I only just realized that there are actually PCIe M.2 storage devices that only support AHCI mode not NVMe. To be fair, there were only a handful of those really early on when M.2 was just getting started and OS/BIOS support for NVMe wasn't universal yet. And hardly any of them were released as retail products; they were mostly OEM-only drives. All of those drives went out of production 3-4 years before the first host devices that require NVMe and can't work with AHCI started to show up: USB to NVMe bridge chips for external enclosures. So if you haven't encountered an AHCI M.2 SSD yet, you probably never will and knowing about them is just an obscure historical curiosity.