Optimizing Video System

The functional capabilities and performance of the video system are determined by the parameters of the monitor, the video adapter, and the software used. Adjusting the monitor using its built-in equipment will generally change the linear dimensions, the distortion compensation of the displayed image, and color, brightness, and contrast correction, etc.

Usually, adjusting the monitor has no impact on the general performance of the video system. Modern video adapters, as a rule, don't have built-in set-up equipment. Normally, their elements never change during operation, except for, maybe, upgrading the video memory and, for certain models of video adapters, the use of a special daughterboard.

However, the video subsystem performance — the speed of processing video information and displaying it on the monitor — and often certain functional capabilities, depend on the settings specified in BIOS Setup — CMOS Setup.

Furthermore, overall performance of the video subsystem depends on the functional capabilities of the installed application software and on the modes set by the operating system and its drivers.

You can access the CMOS Setup immediately after turning on your computer. The system provides you with this opportunity during the POST (Power-On Self Test) by prompting you to press a certain key or key combination to enter the Setup mode.

It may be the key, the key, or a combination like ++, and so on. Usually, this prompt will be displayed on the screen. For example:


Certain versions of BIOS Setup have specific parameters that influence the speed of video output. For instance, if you have Award Modular BIOS (from Award Software), video subsystem performance can be increased by enabling settings such as Video BIOS Shadow and Video BIOS Cacheable.

The BIOS Setup routine provided by certain motherboards allows you to run AGP modes, for example, to enable or disable support of the AGP2x mode and choose the Primary Video (PCI/AGP) option. The choice of the given parameters depends on the type of video adapter used and on the modes that it supports.

In order to support efficient functioning of the video adapter in the 3D modes, some BIOS Setup routines provide special parameters that control the video memory and/or the RAM. For example, the AGP Aperture Size (MB) parameter determines the size of the AGP-video adapter memory.

As with the corresponding option in BIOS Setup, a section of the RAM is dynamically reserved for video adapter. It's usually in this section that the video adapter stores textures. Consequently, the frequency of accessing the hard disk is reduced. The speed of video output is increased as a result.

Setting up the monitor and video adapter drivers should be done according to the documentation supplied with these hardware devices. Often, driver installation and setup is done using special setup programs that come with the hardware.

The performance of the video subsystem is directly related to its operating modes, which are characterized by the color depth and resolution. In the standard VGA/SVGA, the following resolution values have become the most widely used for the most commonly used 14”–17” monitors: 640×480, 800×600, 1024×768, and 1280×1024.

The color palette consists of the following values: 16 colors, 256 colors, High Color (16 bits), True Color (24 bits, 32 bits). For system and office programs, 256 colors are usually enough. For multimedia tasks you may want to use the High Color or True Color mode.

The capabilities of the video subsystem are determined by the video adapter and the size of its video memory, and of course by the quality of the monitor. User requirements are determined by the operating system and installed applications.

Obviously, using a high resolution with a significant color depth will intensify the flow of digital data which the computer video subsystem must process within a limited period of time.

Often, this demands a significant amount of the video adapters as well as of the other hardware components, such as the processor, available RAM, buses, hard disks, etc. Video modes with a low resolution and a small number of colors demand less hardware resources. In this case, the computer processes the video frames considerably faster.

This is particularly important for the tasks related to multimedia information processing. For most modern video clips, playback is optimized for the following video mode: resolution — 640×480, and color palette — 256. It's also possible to use higher resolutions and higher-precision color modes.

The actual capabilities of such modes are limited by the capabilities of the video adapter, the monitor, and by the amount of video memory, which is generally 0.5, 1, 2, 4, 8, 16 MB or more.

Notice that for efficient usage of the video adapter in 3D mode, additional resources such as video memory and RAM are required. These resources are needed for storing textures.

Thus, both the speed of processing and output of video information often decrease, once that extraneous video output parameters have been set. Notice that extraneous parameters will not improve the output quality.

If the video subsystem and other components of the computer don't actually support enhanced video modes, this will result in zoomingin the displayed image.

Also, individual frames may slip out, and/or the image and sound may be distorted. Because of this, to guarantee maximum video performance it is not recommended to set higher-resolution and higher-precision color modes unless it is absolutely necessary.

This is especially true for those cases when you need to provide high performance when using a relatively inexpensive video adapter. It's a well-known fact that the video cards of this class have inferior performance. The power of modern advanced video adapters depends to a great extent on the efficiency of their respective drivers.

Generally, improved versions of the video adapter drivers exploit acceleration features of the card to provide higher video processing and output speed. Sometimes, new drivers even enhance the adapter functionality. Some cases were reported in which upgraded drivers have accelerated video processing and output speed by 30–50%.

This is often more than the actual performance increase generally achieved by replacing the video adapter with the next-generation one (using the new release of the video chipset). Video card manufacturers usually provide comprehensive support for their products through their distributors and dealers.

They are the ones who sell the hardware and software, and take care of consulting and service. Most well known manufacturers provide support for their products for a long time after their release, and are constantly improving drivers and providing new APIs.

Quite often, you can get the necessary advice or download new versions of drivers via the Internet. There you can also find many tips and recommendations concerning video card overclocking using software tools.