|Mr. Fixit's PC Upgrade and Repair
A Graphics card generates a feed of output images to a display or monitor. The earliest versions were known as monochrome graphics
which were limited to 2 colors in the early 1970's. As computers became popular, so did the demand for higher performing graphics cards.
Today, graphic cards can produce millions of colors and create Resolutions as high as 2560 x 1440 pixels of High Definition (HD) video.
Here you will learn the 4 types of graphic cards: IG, IGP, PCI, AGP, and PCI express. Graphic cards are classified as either an Integrated
or Dedicated Graphics.
Integrated Graphics (IG) are made as part of the motherboard and cannot be removed nor upgraded. These are often found in low- to
mid- priced PCs to help PCs become more affordable, compact, simple and have low energy consumption. In most cases, IGs shares
system resources to process video which can be a disadvantage. An IG that shares system resources like System Memory and the CPU
reduce the amount of resources to run other programs and are not recommended for the serious gamer. PC's with Integrated Graphics
can still be upgraded by adding another graphics card using a PCI, AGP, or PCI express version if such expansion is available. If the IG
fails, the motherboard will have to be replaced, however, if there is a secondary graphics card installed, it must be set as the primary video
adapter in BIOS prior to the IGP failure. The only drawback is the reset of BIOS, setting the default video adapter to the IG. Newer BIOS
will automatically switch to the new Graphics card.
Dedicated Graphics are more powerfull than their integrated counterparts. These have there own processor known as the Graphics
Processor Unit (GPU) and their own Memory known as Video RAM, which offloads the CPU and the System Memory. These are often
found in the high-end PCs. Dedicated Graphics are often referred to PCI, AGP or the new PCIe, but did find its way into integrated
Graphics called Integrated Graphics Processor (IGP). Some high-end laptops and Desktops use some form of IGP like AMD, intel, or
nVidia chipsets. Although IGPs are made as part of the Motherboard they have the own Video RAM and GPU. PCs using integrated
Technology will say if their Graphics are either Shared or Dedicated. The following are for use with Dedicated Graphics cards.
Peripheral Component Interface (PCI) graphic cards were only used as an upgrade
from the IGP pc's where an AGP or PCI express slot was not available on the
motherboard. These cards are limited in performance and availability because the PCI
bus only operates at 66MHz with 266MB/s of data transfer rate since PCI version 2.1.
Accelerated Graphics Port (AGP) was created by INTEL for high-performance
graphics and video support. These include AGP, AGP 2X, AGP 4X, and AGP 8X
graphics cards. INTEL released the first AGP in 1996 that operated at 66MHz
transferring 266MB of data per second then later came AGP 2X which transfers 533MB
of data per second. AGP 4X was introduced in 1998 that can transfer 1,066MB of data
per second. Later, AGP 8X was annouced and can transfer 2,133MB of data per
second. The AGP is based on the PCI, but the AGP is physically and electrically
separate from the PCI. AGP 4X and 8X were commonly used by motherboard
PCI-Express (PCIe) is a high-speed serial expansion bus designed to replace the older
PCI and AGP. It was created by several companies, including Intel, Dell, HP, and IBM. It
has numerous improvements over PCI and AGP, including higher maximum system bus
throughput, lower I/O pin count and smaller physical footprint, better performance-
scaling for bus devices, a more detailed error detection and reporting mechanism
(Advanced Error Reporting (AER), and native hot-plug functionality.
PCI and AGP are based on parallel signalling technology where you can send data on
multiple wires at the same time per clock cycle therefore increase data throughput, but
PCIe x16 slot
PCIe x1 slot
All graphic cards contain a Video BIOS, Graphics Processing Unit / Accelerator, Video RAM, Digital-to-Analog Converter (DAC), Bus
connector, and Video drivers. Virtually all graphic cards has 3D acceleration features.
Video BIOS is similar to the PC's BIOS. It contains a set of functions the system can use to communicate with the Hardware. When you
first turn on the PC, you may see the Video BIOS appear briefly showing the name of the card, the amount of Video RAM on it, and the
version of its BIOS. The system uses the Video BIOS to display basic information before any Video Driver is loaded. Video BIOS is
usually upgradable in todays video cards but not often done. Many manufactures would rather update the drivers to fix a problem than
update video BIOS. Video BIOS only gets updated when there is a serious problem in the original programing. No need to update the
video BIOS if one is available by the manufacture unless you are experiencing the problems addressed in the firmware update. The
update may only involve graphic cards installed on a specific motherboard or Operating System.
Graphics Processor Unit (GPU) is also known as a Video Chipset in integrated graphics. The GPU is the heart of any graphics card. It
is similar to the CPU but only process graphics rendering.
Video RAM is the amount of memory installed on the graphics card and is not to be confused with system memory. Many new types of
System memory like the DDR, DDR2, DDR3, etc., were first developed for graphic cards then later turned into System memory. Some of
the high-end graphic cards are testing DDR5 and beyond memory modules. The amount of Video RAM will determine the maximum
resolution and color depth the Video card can deliver. A Video card's video RAM can range from 8MB on the low-end cards to 4GB on
the high-end cards. Many IGPs do not have dedicated memory therefore share the main system memory.
Digital-to-Analog Converter (DAC) is found on graphic cards that provide analog signals like VGA, S-Video, TV-out, etc. The name
says it all. The DAC converts digital images into analog images for non-digital monitors to process. The faster the DAC functions the
higher refresh rates an analog monitor can display. DAC running at 300Hz or higher can provide a refresh rate of 75Hz and above. As
mention with monitors, both graphics card and monitor must support the desired resolution and refresh rate. If the computer has an IGP
built into the motherboard, the DAC is located in the North Bridge.
Bus connector connects the video card to the motherboard by either IGP, PCI, AGP, or PCIe as mention earlier.
Video driver is a software based program that allows communications between a program and the video hardware. It is also the reason
why problems arise. The video driver is only as good as the programmer and yes, errors do creep in. Video drivers are written for a
specific GPU. Each graphics card sold come with its own video driver. Manufactures also use drivers to correct other problems whether
it is a defect in the motherboard, OS, or the card itself. It is not always necessary to update the driver unless you are experiencing the
problems indicated by the update.
SLI and CrossFire
Scalable Link Interface, SLI, was acquired by Nvidia from 3dfx, in 2004. SLI was first used
in 3dfx Voodoo 2 graphic cards. The technology uses two identical graphic cards connected
together, using a Multipurpose I/O (MIO) connector, to render a scene by dividing the work
load between them. SLI offers 2 forms of rendering methods: Split Frame Rendering, SFR,
and Alternate Frame Rendering, AFR. SFR divides the geometry of a frame's work load in
half between the two cards. Using AFR, one card will process the even numbered frames
while the other processes the odd numbered frames in sequence. SLI-Antialiasing is a
stand-alone rendering feature that doubles the antialiasing work load between the two
graphic cards providing superb image quality, but is not intended for higher refresh rates
that will cause low performance. In order to use NVIDIA SLI, you'll need a PCIe motherboard
with SLI-compatible chipset, 2 PCIe x16 slots designed for SLI operation and 2 NVIDIA
GeForce series graphics cards with SLI support (6600, 6800, 7800, etc.). Starting with
ForceWare driver version 81.85, identical cards are no longer necessary to use SLI.
CrossFire was invented by Array Technologies Incorporated (ATI), now AMD, in response
to NVIDIA's SLI technology. CrossFire was introduced in ATI's Radeon (X800, X850, X1800,
etc.) series graphic cards. This started the head butting between ATI and NVIDIA, making
them the top 2 graphics card manufactures. CrossFire incorporates 3 different techniques;
Alternate frame rendering, Supertiling which allows alternating sections to be processed,
and Load-balancing scissor operation (similar to SLI). The earlier Radeons used an
external patch cable to connect the 2 graphic cards. Now using a motherboard with the
CrossFire chipset the PCIe bus can transfer data between the graphic cards. In order to
use ATI's designed for CrossFire operation and 2 ATI CrossFire-supported graphic cards. I
know many of you will probably never use these features but may have heard of them and
didn't know what they were. These features are for the extreme gamers out there and
should only be used to play games compatible with SLI or CrossFire.
upgrade the graphics card but update the drivers or wants to replace the IGP with a better card. Gamers,
such as myself, may need to upgrade to a more powerful graphics card. Todays games require a robust
graphics card. Those who watch videos, DVD, TV, etc. can use a standard graphics card. What to look
for in a graphics card?
|Type of interface in your computer (PCI, PCIe x1 or x16, AGP 4x or 8x, etc)|
|Type of monitor interface (VGA, DVI-I, DVI-D, HDMI, S-Video, TV-out, etc)|
|Certified for your version of Windows|
|System memory requirements|
|Hard disk space requirements for drivers and additional software|
as higher speeds were in demand, it was not possible due to 'cross-talk' interference over longer wires and propagation delays, when all