Advantages of PCIe over PCI | Disadvantages of PCIe, PCI express
This page covers advantages and disadvantages of PCIe over PCI. It mentions benefits or advantages of PCIe and drawbacks or disadvantages of PCIe (PCI Express).
What is PCIe?
• PCI-e or PCIe stands for Peripheral Component Interconnect Express.
• It is high speed serial computer expansion bus which is designed to replace PCI/PCI-X.
• As mentioned PCI express is successor to traditional PCI interface used in desktop PCs.
• PCI express evolutions are PCIe 1.0, 2.0, 3.0, 4.0, 5.0 and 6.0 (planned).
• These versions support different raw data rates (or speed) and bandwidths.
• It supports maximum data rate of 32 GT/s and interconnect bandwidth of 32 Gb/s.
• It is serial interface unlike PCI which was parallel interface.
• PCI express supports more number of devices (~32) on each bus compare to PCI (~5).
The PCIe interface supports hot plugging and uses point to point or shared switch topology. The figure depicts serial interface connection used by PCIe devices to communicate with the switch.
Benefits or advantages of PCIe
Following are the benefits or advantages of PCIe:
➨It is serial technology which provides scalable performance.
➨It offers higher bandwidth and consecutively very fast speed.
➨It is point to point link dedicated to each device instead of PCI shared bus.
➨It offers lower delay or latency as it provides direct connectivity to chipsets.
➨It supports isochronous data transfer.
➨It supports advanced power management.
➨It supports hot pluggability.
➨It is backward compatible with conventional PCI.
➨The higher bandwidth allows smaller form factors and reduction in cost.
➨Moreover it is simple in board design and has less signal integrity issues.
➨Embedded clocking enables easy speed changes as compared to sync clocking.
Drawbacks or disadvantages of PCIe
Following are the drawbacks or disadvantages of PCIe:
➨Bandwidth is not shared unlike PCI bus.
➨PCIe SSDs consume more power when it is used for longer time.
➨Most of the older PCs do not support PCIe SSD.
➨PCIe bus carry different types of data but it does not have any specification.
➨It is expensive to buy SSD drive.