The GPU (Graphics Processing Unit)
Serving essentially as the beating heart of the video card. A GPU is a sophisticated piece of technology dedicated specially to what are called floating-point operations, or 3D graphics rendering. In today's latest and greatest games, a GPU makes it possible to render the fantastic scenery in games like Call of Duty 4, or Crysis, while also doubling as a power center for your videos, lending them a hand whenever you boot up a DVD or play a movie from your hard drive.
The GPU comes in two flavors - Nvidia and ATI. I personally am an Nvidia man, and if you look across the internet, you'll find varied opinions on which one is best. As a rule of thumb, I stick to whoever has the latest technology and has it most readily available. Both companies release excellent products in a constant war of attrition to out-do one another. My next article will show which are the top 5 GPUs along with their respective cards and why.
One final note on the GPU - even though the unit is proprietary technology, both ATI and Nvidia license companies other than themselves to make the graphics (or video) card. It is a fruitless effort to try and find an "nvidia card" - rather, you should focus on finding a specific GPU, like the GeForce 8600 from Nvidia, for instance.
Video RAM holds a special place on the video card specifically for video-memory needs. RAM is most generally known as Random Access Memory, it is an essential part of the computer, moving information from the hard drive into the RAM in order to put it in use, then moving said information back out of the RAM and into the hard drive once more. Video RAM (if not integrated into the motherboard) serves as a special RAM reservoir for all your gaming and video needs - resulting in a crisper, richer experience. As a side note of interest, if you were ever curious as to what disk defragmenters do, aside from re-organizing things layers deep in the magnetic disk of the hard drive, they also push up to the top of the disk the items that you use the most, resulting in an overall speed increase for your computer.
Returning to the point about video RAM, it's actually quite simple and basic to human nature - more is better. However, buying a 2 Gb GeForce 6700 would be about the biggest mistake you could humanly make, which is why it is essential to be a master of balance and buy a good GPU with a good amount of RAM. Of course, the point is to buy a computer that you wouldn't have to re-finance your home to own - and that's likely to happen if you try to buy video cards on the very cutting edge of technology. A final note of advice on buying the card is that any card with less than 256 Mb of RAM is not worth your time and won't play the games you want very well.
The Outputs and Etc.
The outputs are another reasonably simple part of the card - they function to send the signal generated by your computer out to a monitor or projector. There are four basic connectors (in order of quality) S-Video, VGA, DVI-D, and HDMI. If your monitor is new and is part of that "latest and greatest" category mentioned before, you might have an HDMI slot in the monitor, however, most video cards function with the middle two connectors - VGA and DVI-D. Modern monitors have a digital and analog input, the DVI-D will be the digital input and can output resolutions digitally, resulting in a higher-definition experience, the VGA is the analog signal and can output the same resolutions but not with the same crisp-ness of the image. When buying a video card, make sure to check your monitor (and if you have a CRT monitor - don't even bother with the DVI-D connector, as it won't make too big a difference). The card you buy, as long as you buy in a retail package should include both cables (or at the very least a converter).
Ultimately, purchasing the video card is as much a personal experience as purchasing a car or a processor. It's important that you take into consideration what it is that your needs are - if you plan on gaming only a little, it's probably best not to blow your budget on some $500 monstrosity that will only be obsolete a few months from now, rather, buy middle of the road, where the cheapest prices are and where invariably you'll get the best experience. If you game frequently now and think you'll be doing the same when you finally get your rig going, go for something slightly more high-end. My end-all and be-all limit on buying a graphics card is about $250, and will comprise most of the cost of your PC, as will the processor. If you find your eye wandering towards the higher-end cards, just ask yourself if you want to be the one remembering how much you paid for it as you're tossing it out in 18 months.
In the next article, we review the top 5 gaming cards and their respective prices along with the best budget video card out there.