An assembly (for example, an assembly in the form of an interposer that is distinct from a motherboard and from the devices that communicate with the motherboard) includes electromagnetic couplings. Each of the electromagnetic couplings couples signals being communicated between a device and a bus. Each of the electromagnetic couplings is connected to (a) an associated bus connector to provide connections of the couplings to the bus, and (b) an associated device connector to provide connections of the couplings to the device.