Originally, graphics (video) function of a PC was provided by an ordinary PCI video card. Drawing graphics was not a big task and the CPU could handle the load. For intensive applications such as games, the need for a separate graphics subsystem arose and the Accelerated Graphics Port (AGP) was created. The AGP looked like a PCI slot but was used by a special AGP video card. Several iterations of the AGP standard came from AGP 1x to 2x to 4x to 8x. Later, the AGP standard was replaced by PCI Express (PCIe or PCI-E), which is currently universal. Unlike AGP and PCI standard, which used data channels in an exclusivel manner, PCIe standard allowed shared data channels among devices, which could then be grouped or limited dynamically to provide optimum bandwidth. The PCIe standard allowed for a maxium of 32 channels or lanes. A slow device could be given just one lane while a fast device could be theoretically given up to a maximum of 32 lanes.
Most motherboards use 16 lanes for the graphics subsystem. So, what was originally the AGP port is now replaced by a PCIe x16 slot.
nVidia introduced a technology called SLI (Scalable Link Interface) which allowed two PCIe x8 slots to be used by two graphics cards. For gamers, this resulted in great performance improvements because the graphics was rendered by two graphics card working together, instead of just one. ATI, later acquired by AMD, introduced a similar technology called CrossFire, which allowed the use of two ATI graphics cards on two PCIe x8 slots on motherboards using ATI chipsets. PCs using SLI or CrossFire graphic subsystems have significantly higher power requirements and need good cooling setups.
The graphics card if fixed on a PCIe x16 slot on the motherboard and its video-out port will be available on the rear of the cabinet. Older graphics cards have a D-Sub connector that can be used to connect to an analog cable of the CRT monitor. Newer graphics card have a DVI connector that can be used to connect to a digital cable to an LCD screen. However, many LCD monitors only provide D-Sub connections. So make sure your LCD monitor has a DVI connector. Almost all graphics card these days have DVI connectors only.
Apart from this connector, some video cards pack a TV tuner on board. This allows you to connect a CATV (Cable Access TV) cable to the video card and watch television programs. If the video card has a TV tuner, it most likely also has a video-in ports also, which allows you to capture or view video from a video output device such as a VCR or DVD player. Video-In ports could be either serial or composite (RCA) video connectors. (To capture/listen the audio part, you need to connect the audio output to the line-in jack of the sound card.) These cards are also known as VIVO cards. ATI's All-In-Wonder cards are the best VIVO cards on the market.
A company called Aegia has introduced a physics card called PhysX that relieves the graphics subsystem of all the physics-related calculation necessary to render graphics. The Aegia PhysX card comes in the form of a PCI add on card.
Most motherboards use 16 lanes for the graphics subsystem. So, what was originally the AGP port is now replaced by a PCIe x16 slot.
nVidia introduced a technology called SLI (Scalable Link Interface) which allowed two PCIe x8 slots to be used by two graphics cards. For gamers, this resulted in great performance improvements because the graphics was rendered by two graphics card working together, instead of just one. ATI, later acquired by AMD, introduced a similar technology called CrossFire, which allowed the use of two ATI graphics cards on two PCIe x8 slots on motherboards using ATI chipsets. PCs using SLI or CrossFire graphic subsystems have significantly higher power requirements and need good cooling setups.
The graphics card if fixed on a PCIe x16 slot on the motherboard and its video-out port will be available on the rear of the cabinet. Older graphics cards have a D-Sub connector that can be used to connect to an analog cable of the CRT monitor. Newer graphics card have a DVI connector that can be used to connect to a digital cable to an LCD screen. However, many LCD monitors only provide D-Sub connections. So make sure your LCD monitor has a DVI connector. Almost all graphics card these days have DVI connectors only.
Apart from this connector, some video cards pack a TV tuner on board. This allows you to connect a CATV (Cable Access TV) cable to the video card and watch television programs. If the video card has a TV tuner, it most likely also has a video-in ports also, which allows you to capture or view video from a video output device such as a VCR or DVD player. Video-In ports could be either serial or composite (RCA) video connectors. (To capture/listen the audio part, you need to connect the audio output to the line-in jack of the sound card.) These cards are also known as VIVO cards. ATI's All-In-Wonder cards are the best VIVO cards on the market.
A company called Aegia has introduced a physics card called PhysX that relieves the graphics subsystem of all the physics-related calculation necessary to render graphics. The Aegia PhysX card comes in the form of a PCI add on card.
No comments:
Post a Comment