Video Cards

Introduction

People are living in a three-dimensional space. They know what is up, down,
left, right, close and far. They know when something is getting closer or
moving away. However, the traditional personal computers can only make use of
two dimensional space due to relatively low technology level of the video card
in the past. As the new technology has been introduced to the video card
industry in recent years, the video card can now render 3D graphics. Most of
the PC computer games nowadays are in three dimensions. In addition, some web
sites also apply the use of three dimensional space. This means that they are
no longer a flat homepage, but instead a virtual world. With that added
dimension, they all look more realistic and attractive. Nevertheless, 3D do not
exist in most of the business programs today, but it can be forecasted that it
is not far away.

Many new kinds of video cards have been introduced to the market recently. In
the past, the video card could only deliver two dimensional graphics which were
only in low resolution. However, there has now emerged as a result of high
resolution three dimensional graphics technology. This paper will discuss why
the video card nowadays can process high resolution three dimensional graphics,
but why the video card in the past could only process low resolution two
dimensional graphics. The explanation will be based on some recently developed
video cards such like Matrox Millenium. This paper will also discuss how the 3D
graphic displays on a 2D monitor. Lastly, the video card, Matrox Millennium,
will also be discussed.

Basic principles

In order to understand the recent development of the video card, let\'s
take a look on how a video card works.

The video card is a circuit, which is responsible for processing the
special video data from the central processing unit (CPU) into a format that the
visual display unit (VDU) or monitor can understand, to form a picture on the
screen. The Video Chipset, the Video Memory ( Video RAM ) and the Digital
Analog Converter ( RAM DAC ) are the major parts of a video card.

After the special video data leaves the CPU, it has to pass through four
major steps inside the video card before it reaches the VDU finally. First, the
special video data will transfer from the CPU to the Video Chipset, which is the
part responsible for processing the special video data, through the bus.
Secondly, the data will transfer from the Video Chipset to the Video Memory
which stores the image displayed on a bitmap display. Then, the data will
transfer to the RAM DAC which is responsible for reading the image and
converting the image from digital data to analog data. It should be noted that
every data transfer inside the computer system is digital. Lastly, the analog
data will transfer from the RAM DAC to the VDU through a cable connected between
them outside the computer system.

The performance of a video card is mainly dependent upon its speed, the amount
and quality of the Video Memory, the Video Chipset and the RAM DAC.

The faster the speed, the higher the picture quality and resolution the video
card can deliver. This is due to the fact that the picture on the VDU has to
change continuously, and this change must be made as fast as possible in order
to display a high quality and realistic image. In the process of transferring
data from the CPU to the Video Chipset, the speed is mainly dependent upon the
type and speed of the bus, the mainboard and its chipset.

The amount of the Video Memory is also responsible for the color and screen
resolution. The higher the amount of the Video Memory, the higher the color
depth the video card can render. On the other hand, the type of the Video RAM
is an another factor that affects the speed of the video card.

The Video Chipset is the brain of a video card. It similar to the CPU in the
motherboard. However, unlike the CPU which can be fitted with different
motherboards, certain Video Chipsets can only be fitted with certain video cards.
The Video Chipset is responsible for processing the special video data received
from the CPU. Thus, it determines all the performance aspects of the video card.


The RAM DAC is the part responsible for the refresh rates of the monitor. The
quality of the RAM DAC and its maximum pixel frequency, which is measured in MHz,
are the factors affecting the refresh rates. In fact, a