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| Buying Guides: Graphics Cards |
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The sad truth is that most people are suffering along with outdated video cards simply because it is nearly impossible to keep pace with the industry. Popular manufacturers like nVidia and ATI release updated products ever six to nine months. Even worse, companies try to market so many models with the same product name that not even the most educated of hardware gurus can sort through the marketing agendas. Rest assured, no matter what or when you buy, a better card will be released in just a few weeks time. The video card market is truly an example of trickle-down economics. Video cards are consistently decreasing in value considering the fast pace of hardware development. The same card that sold for $600 only six months ago can now be found for $200 or less! While gamers will no doubt seek out the most expensive cards available, often well into the hundreds of dollars, most average desktop users should be able to slide by with a more affordable card. Through this guide we refers to various technical specifications. We recommend reviewing the popular "Table of Graphics Chips" for explanations of video card features. Also take note that many retail brands exist, but the most video cards are powered by a chipset that’s made by only a select few manufacturers: ATI, Matrox, nVidia, SiS, etc. 2D Graphics: Resolution, Color, and Quality Video cards work in the world of pixels. Each pixel essentially represents a single dot on the display screen. Displays are sized according to resolutions, or horizontal pixels multiplied by vertical pixels. Most users rely upon sizes ranging from 1024x768 to 1600x1200 depending upon the size of the system’s monitor. An additional variable is also represented in the form the color depth. The 32-bit depth (16.8 million colors) has long been considered the defacto industry standard, though current generation cards can support values ranging from eight to 32 bits. Gone are the days of concerning ourselves with 2D graphics performance, as even the most inexpensive of graphics accelerator will run your favorite desktop application like Microsoft Word or Internet Explorer. If 2D image quality is a required consideration, then you will need to take note of a video card’s RAMDAC frequency. The general rule is the higher the MHz, the higher resolution and bit-depth a card can support. The best 2D cards will feature a 400 MHz rating, such as the Matrox Parhelia or ATI Radeon 9x00 (9600, 9700, 9800, etc) series. At minimum, a 350 MHz RAMAC is recommended. The physical connection between a video card and monitor can also influence display quality. Most CRT monitors support a standard analog DB15 connector; the same plug that has been in use for over a decade. The latest LCD displays use a digital DVI-I connector. If you intend to use a LCD display, then DVI is a must for preserving maximum image quality with no artifacts or other minor screen corruptions. Most video cards offer a combination of analog and digital connectors, or at least a converter to switch among the two formats. 3D Graphics: Memory
As with memory, the AGP bus standard is often misunderstood as well. A higher transfer rate does not always translate into improved performance. Video cards with 128MB or more of memory rarely have a need to transfer textures across the AGP bus, plus the original AGP specification provided more than enough bandwidth for transferring other data such as geometry due to the small amounts of information involved. The latest generation of cards supports AGP 8x, though most 3D enthusiasts still often consider AGP 4x as the default standard. Either are acceptable, just don’t expect a performance increase beyond 3-5% for an 8x card verses a 4x card. Consumer-class cards are backwards compatible, meaning an 8x card will work perfectly fine with a motherboard supporting only 4x transfers. 3D Graphics: Fill Rate and Bandwidth Simple MHz ratings cannot be used for determining a video card’s performance. Differences in memory types, pipeline stages, and bit levels all attribute to a card’s performance potential. The two specifications of particular interest are fill rate and bandwidth. Even though these two measurements only represent the maximum theoretical performance, they can offer plenty of information when trying to navigate through the myriad of cards available today. Simply put, higher fill rate and bandwidth values translate to improved performance. With the complexity of current games, one should stay above certain thresholds when purchasing a video card to guarantee decent performance at 1024x768 and above with advanced filtering techniques enabled. Rendering performance is measured in two distinct values: pixels and texels per second. A value of 1300 is the recommended minimum for both, though 2000+ is suggested for extremely high resolution gaming at 1600x1200 and beyond. As to memory, a decent mid-range card will offer 9 Gigabytes per second or better bandwidth. 3D Graphics: Pixel/Vertex Shading Just three years ago, the consumer video card market was revolutionized with the introduction of hardware-accelerated transform and lighting or hardware T&L. A video card with a hardware T&L engine can significantly offload the processing of complex geometry data from your PC’s processor, thus freeing up resources for other gaming tasks like artificial intelligence or physics calculations. Advanced shading techniques were recently engineered to create dynamic effects not possible with hardware T&L engines. Two types of shaders are represented by Microsoft’s DirectX architecture, the choice of most popular game developers. Various shader implementations exist, but a video card with both hardware vertex and pixels shaders, regardless of the version number (1.1-2.0+), is strongly recommended as games with DX9 support are starting to emerge on the marketplace. AGP versus PCI Many entry-level desktop systems rely upon comparatively slow graphics chipsets that are integrated into the motherboard’s chipset. 3D performance with these systems is normally sub-par regardless of how impressive the overall system’s specifications (processor, memory, etc.) may be. The positive aspect is that most manufacturers include an AGP slot for upgrading to a standalone graphics accelerator. The negative aspect of motherboards with integrated graphics chipsets is that some entry-level systems from volume retailers like Dell and HP lack an AGP slot, thus complicating future upgrades. In these cases, a video card designed for the older PCI bus standard must be installed instead. The PCI bus is many times slower than its AGP counterpart, so it is important to purchase a card with plenty of onboard memory (128MB+) to minimize texture transfers. The ATI AIW Debate All-In-Wonder style cards have become popular in recent months. These video cards bundle an entire video input/output system into a single board setup, such as support for a TV tuner, input video recording, and an assortment of other neat tricks. AIW-type cards demand a premium over their counterparts, and keep in mind that a standalone low-cost TV tuner board can often reproduce the same functions as an AIW card, assuming you have a spare PCI (or external USB) slot.
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Did
you just pick up a copy of Call of Duty only to find its looks like
a pixilated blob as it scrolls across the screen in a slow crawl?
Or maybe you want to play the much-anticipated Doom III when it ships
in 2004? Either way, there is a good chance your current video card
will fail miserably in trying to render the latest generation of detailed
3D games.