Adding or upgrading a Video Graphics Card can be one of the most rewarding purchases you can make for your PC. The added power of a new video card will improve your systems performance more than just about any other upgrade. Choosing the right model for your needs however can be a bit daunting. Our Buyer’s Guide will help to make you a savvier consumer and help you navigate the through the wide array of Graphics Cards available today. Becoming a savvy shopper means not only knowing your budget but also asking yourself the right questions about how your graphics processing needs. Here are some questions to keep in mind as you work through our buyers guide:

• What is my budget?
• What kind of applications do I mainly run?
• What kind of expansion slot does my PC have?
• What kind of connections might I need?
• How many monitors do I plan to run?

With some of these questions in mind, we will now take you step by step through the some of the most important aspects of choosing a Video Graphics Card most suitable for your needs.

Host Interface

A video card is installed into a special expansion slot on a motherboard. The video card uses this slot to exchange information with a PC processor. There are three different types of expansion slots: PCI, AGP and the newer PCI-E. They differ in bandwidth, voltages, and other characteristics, and not all of them can accommodate differing video cards. It's very important to know what slots you have on your PC's motherboard and buy a video card accordingly. Different expansion slots are incompatible physically and logically. A video card designed for one slot type cannot be installed into a slot of another type. Below we will discuss the three types:

PCI

The PCI slot was developed first and is the most limited in terms of performance. However, if you are looking for a value-level video card, there are many excellent PCI cards available that offer great performance for the money.

AGP: Accelerated Graphics Port

AGP was introduced as a higher-speed alternative to PCI display adapters, and it freed a PCI slot for another peripheral device. The brown AGP slot is slightly shorter than the white PCI slot and is located about an inch farther back. AGP is superseded by PCI Express.

PCI-E: PCI Express

The PCI Express, also known as PCI Express x16, is the newest slot type and offers performance as much as 4X faster than the fastest AGP 8X slot. Nowadays more PCs come standard with at least one PCI Express x16 slot type. Although the names are similar, PCI Express is separate and different from PCI. They are physically different shapes and use different standards of data transfer. A PCI Express video card will not fit into a PCI slot and vice-versa. Initially used for high-speed display adapters, and intending to eventually replace the PCI and AGP buses entirely, PCI Express was designed to match the higher speeds of today's CPUs. It can accommodate Gigabit and 10 Gigabit Ethernet and even support chip-to-chip transfers.

Processor Speed

The GPU (graphics processing unit) is a small microchip present on most modern graphics cards. They are specifically designed for processing complex, graphical algorithms that previously fell to the CPU. Thus, they both take the strain off the main CPU, and process information faster thanks to specialized design.

GPU Processing is measured in megahertz, millions of cycles per second. This directly affects GPU performance. The higher it is, the more vertices and pixels can be processed by a graphics processor per second. In terms of rendering speed, the per-clock performance of the graphics processor is indicated by the number of pixels it can process per cycle.

Below is a performance breakdown of what you might expect based on processing speed of the GPU.

• 166MHz - 300MHz
• basic web browsing
• working with single documents
• basic level use

• 325MHz – 600MHz
• watching video
• light multitasking
• gaming
• Digital Photography

• 625MHz and more
• video editing
• hard core gaming
• high-end video
• heavy multitasking
• working with multiple documents
• Running two or more monitors

Memory size

Measured in Megabytes (MB), this is the amount of memory on the graphics card, to be used exclusively for graphics operations. The job of the video memory is to store images processed by the GPU before they are displayed by the monitor. The larger the video memory, the better the graphics card can handle textures when displaying 3D scenes. The effect of memory size on performance will vary depending on the application. The graphics processor can talk to the graphics card's memory much quicker than it can talk to the PC's memory, so the more memory on board, the less it has to go to main memory for the information it needs to render a scene. Below is a rough breakdown of what applications you might expect based on the memory size:

• Up to 64MB
• basic web browsing
• working with single documents
• basic level use

• 64MB – 256MBz
• watching video
• light multitasking
• gaming
• Digital Photography

• 512MB and more
• video editing
• hard core gaming
• high-end video
• heavy multitasking
• working with multiple documents
• Running two or more monitors

Bus Width

Measured in bits, memory bus width is a important factor to consider when purchasing a video card. A wider bus allows a higher rate of data transfer from the video memory to the GPU which, in most cases will have a positive effect on performance. Below is a rough breakdown of what applications you might expect based on the memory size:

• Up to 64bit
• basic web browsing
• working with single documents
• basic level use

• 128bit – 256bit
• watching video
• light multitasking
• gaming
• Digital Photography

• 320bit and more
• video editing
• hard core gaming
• high-end video
• heavy multitasking
• working with multiple documents
• Running two or more monitors

Summary

With price points continually coming down and feature sets continually going up, it is a great time to purchase a Graphics Card. With all of the above considerations in hand you should now be better equipped to make an more informed choice when choosing a Graphics Card that best suits your needs.