What also makes PCIe interesting is that it replaces the widespread use of parallel buses with serial links. Instead of having a bus with a common medium (traces) to which multiple devices connect ...

The bus in a PC is the common hardware interface between the CPU and peripheral devices. Parallel buses with multiple lines (wires) were superseded by serial versions, which use one line for data.

The I/O bus from the CPU to the peripherals is a parallel bus (16, 32 or 64 wires, etc.). Although sounding similar, a serial bus differs from a serial port. Both use serial transmission ...

Traditionally, the I/O- subsystems are connected to the CPU through the PCI or PCI-X bus. But it is getting more and more difficult to improve the performance with a multi-drop parallel bus such as ...

With advanced silicon process technology, the interfaces for these serial links have become small enough, and the data rates high enough, that multi-Gbps serial links are replacing parallel buses, and ...