Monday, March 19, 2001		On Hardware

Video cards improve computer performance
By Naveen S. Garewal

ONE single computer component that can affect your computer performance the most while performing high-end graphic applications is a video or a graphics card (the two terms are used interchangeably). A slow and outdated graphics card can act as an impediment irrespective of the amount of memory in the system or the latest generation of processor installed. If you are buying a new computer or even upgrading an older system, it is imperative that you have a look at the video card that is installed in the machine.

The video card is the piece of hardware that produces the visual output on the computer monitor and tells the display device what to show on the screen and in which colour. Earlier video cards displayed only what the central processor wanted them to, but today the video cards themselves contain small chips that act like independent brains, thereby taking onto themselves a lot of work that would have otherwise been done by the main processor. This reduces stress on the central processor.

Without going into great details, it is important to mention that a good video card can be a "sight saver", while a poor quality video card with low refresh rate can not only slow down the system, but also throw up poor quality image that can cause eyestrain and fatigue.

Video card manufacturers have had a competition that can be rated as much stiffer that the main processor manufacturers and in the last few years graphic cards have progressed from ones working on 256 KB memory to 64 MB on board memory today. Some time back 2 MB of memory on a video card was something to show off, but video cards have come a long way from ISA, VL, PCI bus standards and the various variants of AGP that are currently available.

The role of the video card changed over the time due to the increase both in the manner and quantity of data that went to the monitors. Particularly so after the introduction of 2D and 3D computing. A good video or graphic card not only positively impacts the system performance, but has also become essential for support to many high-end software including games and graphic applications like designing. A 3D game would not run on a system that does not have a video card that supports standards like D3D and Open GL used in gaming.

Luckily for first-time computer users, most motherboards in the market today have an on board video card that suffices for average graphic applications, including games that use medium graphic applications. But for those who really want power performance from their system, choosing the right video card is vital as video or graphic cards are notorious for causing a major threat to system stability. Choosing the wrong video card with unstable drivers can cause severe problems in system behaviour and lead to system crashes.

Since, a graphic card acts like a middleman between the processor and monitor, it is important to understand how this hardware works. Since earlier cards acted as dumb pieces of hardware and put up on screen whatever the main processor wanted, they were OK in environments like DOS and UNIX, but with operating systems become more intelligent, they expected the same from the graphic cards. To clear this bottleneck companies began making cards called accelerators; in fact, Windows drove this effort so much that they were often called Windows accelerators.

These accelerator cards did a lot of calculations by themselves and boosted performance, as it game time to the processor to do more useful work. This offloading of video calculation work has led to a many fold increase in the power of the video subsystem in a modern PC. Every video card in the market today has incorporated acceleration.

Starting from a couple of hundred rupees, the video cards available in the market go up to several thousand, depending on the technology they support and the functions they can perform. Some video chipmakers have emerged clear leaders over the others and almost every software manufacturer tests its software on these chips before releasing its final edition of the software.

Nowadays, graphics processors, or GPUs (Graphics Processing Unit) to use the term popularised by NVidia, typically run at up to and around 200MHz. Video memory can run at an effective 300-400MHz by using DDR SDRAM that really runs at 150-200MHz and doubles its speed to 150-200MHz*2 for a faster effective throughput. Typically, the faster the chip and memory are running at, the better performance you’ll get.

Nvidia and ATi have over the years emerged as the top dogs in video card production. 3Dfx technology that ruled the market for a long time is now out of the reckoning. TnT series of video cards by Nvidia secured an edge over the ATi and with the release of the Geforce, Nvidia in some ways, revolutionised gaming standards.

After a simple start the Geforce evolved into the DDR board versions, then took on some more RAM, went further and became the GTS, and now finally we have the PRO and ULTRA. The latest is GeForce3 that is the first programmable AGP card, which actually tells the game engine the manner in which the graphics should be displayed.

The best 2D and 3D performance go with either the NVidia GeForce2 GTS or ATI Radeon, either one with 64MB of DDR (Double Data Rate) memory. A Taiwanese company, Palit, has made produced a TNT2 M64 chip based card and put it in the Indian market at around Rs 3800. The card named Palitdaytona has 32MB of SDR (Single Data Rate) memory on board. This is an excellent value for money when you consider that a GeForce2 MX costs close to Rs 7500.

Palitdaytona is a high performance 128 bit 2D/ GUI / Directdraw accelerator that works on a AGP 4X/2X interface on a 64 bit frame buffer interface with integrated 300 MHz RAMDAC and is available in both normal and TV out models. The high quality 3 D features of this card include 1.2 GB/ sec total memory bandwidth, 128 bit TNT architecture, 32 bit 3 D rendering with DrirectX 7.0 and open GL support required for most games.

Depending upon your requirement, video cards come with an array of options such video output, or an S-Video output. This is handy if you want to hook your PC up to a large colour television for game playing or a VCR Other features include video inputs and TV compatible features. With this type of card, you can watch TV in a window on your computer monitor.

The biggest advantage of using graphic cards based on TNT (TwiN-Texel) architecture chip is that all such cards use one driver for all cards. These drivers called detonator drivers can be downloaded and upgraded periodically from Nvidia homepage to get the best performance from you graphic card.

Also, before buying any graphic card make sure that the manufacturer has a presence on the web. This will allow you to download the latest drivers for the card, so that you can download drivers for various software.