With the Prom21, WisdPi is bringing a manufacturer-independent expansion card with AMD's B650 desktop chipset to market for the first time. It is primarily intended as an internal PCI Express card (PCIe 4.0 x4) for desktop PCs, but fundamentally works in and with all sorts of systems.
According to the developer, it even works with a Thunderbolt 5 adapter on Apple Macs and with an M.2 adapter on a Raspberry Pi 5. Standalone drivers are apparently not necessary; the generic drivers of current operating systems should suffice.
Extra USB, SATA, and M.2
Modern chipsets are simply I/O hubs that communicate with the processor via PCI Express and provide further connections. The Prom21 card from WisdPi offers one USB 3.2 Gen 2x2 (20 Gbit/s, Type C), four USB 3.2 Gen 2 (10 Gbit/s, Type A), four M.2 slots, and an Oculink port. The latter can be used to connect up to four SATA drives via an adapter cable, for example. There are also six USB 2.0 front headers for case connections.
According to the documentation, the M.2 slots are each connected with four PCIe 4.0 lanes. However, as with motherboards, the PCIe connection to the processor is a limiting factor: the SSDs can achieve high speeds individually but cannot be fully utilized simultaneously.
