Specifications

Video Display Adapters
901
Figure 15.11 A typical example of a high-end video card based on the NVIDIA GeForce FX 6800 Ultra
GPU, a GPU optimized for gaming and dual-display support.
Virtually all video adapters on the market today use chipsets that include 3D acceleration features.
The following sections examine these components and features in greater detail.
The Video BIOS
Video adapters include a BIOS that is similar in construction but completely separate from the main
system BIOS. (Other devices in your system, such as SCSI adapters, might also include their own
BIOS.) If you turn on your monitor first and look quickly, you might see an identification banner for
your adapter’s video BIOS at the very beginning of the system startup process.
Similar to the system BIOS, the video adapter’s BIOS takes the form of a ROM (read-only memory)
chip containing basic instructions that provide an interface between the video adapter hardware and
the software running on your system. The software that makes calls to the video BIOS can be a stand-
alone application, an operating system, or the main system BIOS. The programming in the BIOS chip
enables your system to display information on the monitor during the system POST and boot
sequences, before any other software drivers have been loaded from disk.
√√ See “BIOS Basics,” p. 398.
The video BIOS also can be upgraded, just like a system BIOS, in one of two ways. The BIOS uses a
rewritable chip called an EEPROM (electrically erasable programmable read-only memory) that you can
upgrade with a utility the adapter manufacturer provides. On older cards, you might be able to com-
pletely replace the chip with a new one—again, if supplied by the manufacturer and if the manufacturer
did not hard solder the BIOS to the printed circuit board. Most recent video cards use a surface-mounted
BIOS chip rather than a socketed chip. A BIOS you can upgrade using software is referred to as a flash
BIOS, and most current-model video cards that offer BIOS upgrades use this method.
Video BIOS upgrades (sometimes referred to as firmware upgrades) are sometimes necessary in order to
use an existing adapter with a new operating system, or when the manufacturer encounters a signifi-
cant bug in the original programming. Occasionally, a BIOS upgrade is necessary because of a major
revision to the video card chipset’s video drivers. As a general rule, the video BIOS is a component
that falls into the “if it ain’t broke, don’t fix it” category. Try not to let yourself be tempted to upgrade
just because you’ve discovered that a new BIOS revision is available. Check the documentation for the
upgrade, and unless you are experiencing a problem the upgrade addresses, leave it alone.
√√ See “Video Adapter BIOS,” p. 523.
Chapter 15
AGP 4x/8x slot connector
Heatsinks over GDDR-3 memory chips
Power connector for fan
Cooling fan over 6800 Ultra GPU
GDDR-3 memory chips
Connectors to system power supply
TV-out (S-video)
DVI-out (can be
converted to VGA-out)
16 1738 ch15 7/30/04 10:31 AM Page 901