Integrated Graphics Subsystem

6.2 Functional Description

The Intel 915G/GV GMCH component includes an integrated graphics controller (IGC). (Figure 6-1). The IGC can directly drive an external, analog multi-scan monitor at resolutions up to and including 2048 x 1536 pixels. The IGC includes a memory management feature that allocates portions of system memory for use as the frame buffer and for storing textures and 3D effects.

The IGC provides two SDVO channels that are multiplexed through the PCI Express graphics interface. These SDVO ports may be used by an Advanced Digital Display (ADD2) card installed in the PCI Express graphics slot in driving two digital displays with a 200-megapixel clock.

The SSF, ST, MT, and CMT sytems may be upgraded by installing a separate PCI-E graphics card in the PCI Express x16 slot, which disables the onboard IGC. All systems may be also be upgraded by installing a PCI graphics card in teh PCI 2.3 slot.

 

 

 

 

 

 

82915G/GV GMCH

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DDR

 

 

RGB

Integrated

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SDRAM

 

 

 

 

 

Monitor

Graphics

 

 

 

 

 

 

 

 

 

SDRAM

 

 

 

 

 

Controller

 

 

 

 

Controller

 

 

 

 

 

(System

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Memory)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PCI-E

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PCI Express x16

 

& SDVO Data

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PCI Expr. I/F [2]

 

 

 

 

 

 

 

 

Graphics slot [1]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NOTE:

[1]SFF, ST, MT, and CMT form factors only

[2]82915G GMCH only

Figure 6-1. 915G-Based Graphics, Block diagram

The Integrated Graphics Controller provides the following functions:

■Rapid pixel and texel rendering using special pipelines that allow 2D and 3D operations to overlap, speeding up visual effects, reducing the amount of memory for texture storage.

■Zone rendering for optimizing 3D drawing, eliminating the need for local graphics memory by reducing the bandwidth.

■Dynamic video memory allocation, where the amount of memory required by the application is acquired (or released) by the controller.

■Intelligent memory management allowing tiled memory addressing, deep display buffering, and dynamic data management.

■Provides two serial digital video out (SDVO) channels for use by an appropriate ADD2 accessory card.

6-2

361834-002

Technical Reference Guide