/ˌeɪ-dʒiː-ˈpiː/
n. “The dedicated graphics highway of early PCs.”
AGP, short for Accelerated Graphics Port, is a high-speed point-to-point channel introduced in 1997 for connecting graphics cards to a computer’s motherboard. It was designed specifically to improve the performance of 3D graphics by providing a direct pathway between the GPU and system memory, bypassing the slower shared PCI bus.
Key characteristics of AGP include:
- Dedicated Graphics Channel: Ensures the GPU has a direct, high-speed connection to system memory.
- Multiple Data Rates: Versions include 1x, 2x, 4x, and 8x, with higher multipliers increasing throughput.
- Texture Memory Access: Allows the graphics card to fetch textures directly from system RAM, improving 3D rendering performance.
- Point-to-Point: Unlike PCI, which is a shared bus, AGP provides a dedicated link for graphics data.
- Legacy Technology: Replaced by PCI Express (PCIe) starting in the mid-2000s.
Conceptual example of AGP usage:
# Installing a 3D graphics card in a 2002 desktop
Desktop motherboard has AGP 4x slot
GPU fetches textures directly from system RAM via AGP
3D rendering performance improved over PCIConceptually, AGP is like giving your graphics card its own dedicated highway to memory instead of sharing a congested main road with other devices.
In essence, AGP was a pivotal step in 3D graphics acceleration, providing higher bandwidth and better performance than PCI, until it was superseded by the more flexible and faster PCIe standard.