Introduction
Similar to the promises of dual core processors, having multiple graphics cards working cooperatively is supposed to provide improved 3D performance over a single graphics card. Both major video card manufacturers, ATI and NVIDIA, both offer solutions for running two graphics in this manner. But are the solutions worth it for the consumer? This article looks at the requirements of the different solutions, the benefits of the solutions and whether consumers should really consider looking at such a solution.
Requirements
In order to use multiple graphics cards, there is underlying hardware that is required by both ATI and NVIDIA in order to run their graphic cards solutions. ATI's graphic solution is branded CrossFire while the NVIDIA solution is named SLI. For each of these solutions, a compatible motherboard for the appropriate chipset is needed. Without one of these motherboards, having multiple cards isn't an option.
Once the consumer has a compatible motherboard, there are also restrictions upon what graphics cards can be used together. Originally, NVIDIA required that two identical cards from the same manufacturer, model type and BIOS were needed to function in SLI. They have eased these requirements since then but the same graphics chip model is still required. As for ATI, a special CrossFire master graphics board is required to connect to a second card. This card typically costs more than a non-master board. This card can be used with almost any previous generate ATI graphics board, but performance improvements will vary depending upon the second or slave board.
Benefits
There are two real benefits of being able to run multiple graphics cards. The primary reason is for increased performance with 3D applications, aka games. By having two graphics cards sharing duties at rendering the 3D images, PC games can be run at higher frame rates, higher resolutions and with additional filters. This can dramatically improve the quality of the graphics within these games.
The other benefit is for people who want to upgrade at a later point and time without having to completely replace their graphics card. By purchasing a graphics card and motherboard that are capable of running multiple cards, the user has the option of adding in a second graphics card at a later point and time to boost performance without having to completely remove his existing graphics card.
Disadvantages
The big disadvantage to running multiple graphics cards is the cost. With the top of the line graphics cards already pushing $500, its very tough for consumers to be able to afford a second one. While both ATI and NVIDIA offer lower priced cards with the dual card capability, it is often better for the consumer to instead spend an equal amount of money on a single card with equal or sometimes better performance than two graphics cards.
The other problem is that not all games can benefit from the multiple graphics cards. Some graphics engines were just not developed to properly utilize the multiple graphics core. In fact, some games might actually show a slight decrease in performance over a single graphics card. As newer games are released, this is becoming less of an issue. New games might not immediately benefit from the two cards as the graphics card drivers have to be updated to utilize the multiple cards correctly for improved performance.
Finally, the actual performance benefits of having the multiple graphics cards can vary greatly depending upon the other components in the computer system. Even with two of the highest level graphics cards, a low end processor can throttle the amount of data the system can provide to the graphics cards. As a result, dual graphics cards is typically recommended only in higher end systems.
Conclusions
For the average consumer, running multiple graphics cards makes absolutely no sense. The overall costs of the motherboard and graphics cards, not to mention the other core hardware necessary to provide sufficient speed for the graphics is just way too much. This solution only really makes sense to those individuals who want to have bragging rights on having one of the fastest graphics platforms possible, but similar user experiences in these games can be had for much less.
Some people might benefit from the multiple graphics cards though. Users who do periodically upgrade their components rather than replacing their computer system may want to look into having the option for upgrading their graphics card with a second card. This can be an economic benefit to the user provided a similar graphics card is available and has dropped in price from the initial cards purchase.
