These modems would often slot into a Mini PCI-e slot in the netbook motherboard. [delokaver] figured out how to use these 3G cards over USB instead. It’s actually a fairly straightforward hack.
Ever since people figured out that the Raspberry Pi 4 has a PCIe bus, the race was on to be the first to connect a regular PCIe expansion card ... USB 3 ports useless, one can still use the USB-C ...