Short for accelerated graphics port, AGP is an advanced port designed for video cards and 3D accelerators. Developed by Intel and introduced in August 1997, AGP introduces a dedicated point-to-point channel that allows the graphics controller direct access to the system memory. Below is an illustration of what the AGP slot may look like on your motherboard.
The AGP channel is 32-bits wide and runs at 66 MHz, which is a total bandwidth of 266 MBps and much greater than the PCI bandwidth of up to 133 MBps. AGP also supports two optional faster modes, with a throughput of 533 MBps and 1.07 GBps. It also allows 3-D textures to be stored in main memory rather than video memory.
AGP is available in three different versions, the original AGP version mentioned above, AGP 2.0 that was introduced in May 1998, and AGP 3.0 (AGP 8x) that was introduced in November 2000. AGP 2.0 added 4x signaling and was capable of operating at 1.5V, and AGP 3.0 was capable of double the transfer speeds.
Where is AGP on the motherboard
Today, AGP has been replaced by PCI Express.
A computer with AGP support has one AGP slot next to all other expansion slots or an onboard AGP video. If you needed more than one video card in the computer, you can have one AGP video card and one PCI video card or use a motherboard that supports SLI.
Not all operating systems support AGP because of limited or no driver support. For example, Windows 95 did not support AGP.
What is AGP Pro?
AGP Pro is an AGP interface extension specification for advanced workstations. This specification delivers additional power to video cards, includes an extended connector, thermal envelope, mechanical specifications, I/O bracket, and motherboard layout requirements.