<Tr> <Th> Hotplugging interface </Th> <Td> Yes, if ExpressCard, Mobile PCI Express Module, XQD card or Thunderbolt </Td> </Tr> <Tr> <Th> External interface </Th> <Td> Yes, with PCI Express External Cabling, such as Thunderbolt </Td> </Tr> <P> PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe or PCI - e, is a high - speed serial computer expansion bus standard, designed to replace the older PCI, PCI - X, and AGP bus standards . PCIe has numerous improvements over the older standards, including higher maximum system bus throughput, lower I / O pin count and smaller physical footprint, better performance scaling for bus devices, a more detailed error detection and reporting mechanism (Advanced Error Reporting, AER), and native hot - plug functionality . More recent revisions of the PCIe standard provide hardware support for I / O virtualization . </P> <P> The PCI Express electrical interface is also used in a variety of other standards, most notably the laptop expansion card interface ExpressCard and computer storage interfaces SATA Express and M. 2 . </P>

What type of bus does pci express use