PCIe real connection to devices

The general case is the one you mentioned with a single Endpoint alone on its bus, as the whole point of PCIe was to move to point-to-point physical links.

I can think of two specific cases with multiple Endpoints on a bus (there might be more):

1. Integrated Endpoints inside the Root Complex, which are all connected to the internal bus
2. Legacy PCI Endpoints behind a PCIe-to-PCI bridge, all on the same PCI bus

If you consider not only Endpoints but Devices: the PCI-to-PCI virtual bridges inside a switch or in the Root Ports are also all connected to a single internal bus.

The general case is the one you mentioned with a single Endpoint alone on its bus, as the whole point of PCIe was to move to point-to-point physical links.

I can think of two specific cases with multiple Endpoints on a bus (there might be more):

1. Integrated Endpoints inside the Root Complex, which are all connected to the internal bus
2. Legacy PCI Endpoints behind a PCIe-to-PCI bridge, all on the same PCI bus

If you consider not only Endpoints but Devices: the PCI-to-PCI virtual bridges inside a switch or in the Root Ports are also all connected to a single internal bus.