PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe or PCI-e,[1] 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.
The PCI Express electrical interface is also used in a variety of other standards, most notably in ExpressCard as a laptop expansion card interface, and in SATA Express as a computer storage interface.
Format specifications are maintained and developed by the PCI-SIG (PCI Special Interest Group), a group of more than 900 companies that also maintain the conventional PCI specifications. PCIe 3.0 is the latest standard for expansion cards that are in production and available on mainstream personal computers.
Alternatively referred to as an add-on card, expansion board, internal card, interface adapter, or card, an expansion card is a PCB that fits into an expansion slot on a desktop computer. An expansion card is used to give a computer additional capabilities, such as enhanced video performance via a graphics card.
Sound Card- A sound card (also known as an audio card) is an internal expansion card that provides input and output of audio signals to and from a computer under control of computer programs. The term sound card is also applied to external audio interfaces used for professional audio applications. Typical uses of sound cards include providing the audio component for multimedia applications such as music composition, editing video or audio, presentation, education and entertainment (games) and video projection.
Sound functionality can also be integrated onto the motherboard, using components similar to those found on plug-in cards. The integrated sound system is often still referred to as a sound card. Sound processing hardware is also present on modern video cards with HDMI to output sound along with the video using that connector; previously they used a SPDIF connection to the motherboard or sound card.
Graphics Card-
A Graphics Card is a piece of computer hardware that produces the image you see on a monitor.
The Graphics Card is responsible for rendering an image to your monitor, it does this by converting data into a signal your monitor can understand.
This is naturally very important for gamers and video editors.
