TL;DR
O_MORES on Reddit has come up with a clever solution to connect a modern NVMe solid-state drive (SSD) to a vintage computer that only has PCI (Peripheral Component Interconnect) slots. The process involves using an M.2-to-PCIe Add-in Card (AIC) to house the NVMe SSD. This AIC is then inserted into a PCIe-to-PCI adapter, allowing it to fit into the older PCI slot on the motherboard. Although PCI and PCIe have different pinouts and are physically distinct, they can be used together because they are logically compatible.