Multiple graphics cards can yield particularly superb results if each device is given a specific role.
Two Is Better than One!
Using a single video card in your PC gives you graphics and video for playing games and enjoying high definition movies.
But what happens when you use two video cards? If your PC has two suitable PCIe slots this is a possibility.
Many video cards can be run in tandem – some ATI cards have Crossfire compatibility, while nVidia video adaptors can be paired, with one acting as a dedicated physics card and the other fulfilling the typical graphics card role, using the PhysX system.
This enables more efficient processing of in-game physics on one card and allows the other to focus on generating graphics.
What Does PhysX Add to Gaming?
As its name suggests, PhysX adds physical realism to games, allowing one graphics processor to be used as a physics engine to calculate in-game physics. This might be something like the force of an explosion on your main character or surrounding debris, or the damage from a bullet.
PhysX is present on single, suitable cards from nVidia; however with the configuration of one video card as a physics card and the other retained as a graphics card, PhysX performs better in compatible games.
With this sort of added realism, video games can become even more intense and powerful. Some of the top games over the last couple of years have made use of the PhysX system to create a fuller, immersive gaming experience.
This has allowed nVidia to sell a lot of video cards supporting PhysX. You can tell which cards support PhysX from the device packaging; nVidia graphics chipsets are used by many card manufacturers.
Supported PhysX Games
Some great games support the PhysX system and can therefore take advantage of the enhanced physical realism provided by setting a video card as a physics card. They include the popular Batman: Arkham Asylum, one of the biggest games of the last two years and Mafia II.
Physics effects are often times limited to a handful of specific graphical effects, but these few effects are impressive. In Batman: Arkham Asylum, for example, the PhysX can be used to make Batman's cape behave in a realistic manner rather than flopping about in a pre-ordained pattern. This improves the look of the game's main character.
These are just a couple of the games that support PhysX. If your PC or laptop uses a suitable graphics cards from nVidia then these games will play slightly differently to how they might with an ATI graphics card (however, with the right drivers you can take advantage of PhysX with an ATI card if you use a second nVidia branded card for physics only).
Configuring Your Video Card as Physics Card
With your intended dedicated PCIe graphics card installed in the graphics slot on your motherboard, the second video card should be installed either in a secondary PCIe graphics slot or in a standard PCIe slot.
When you boot into Windows, the new graphics card should be detected automatically and install. Once this has completed all you then need to do is find the nVidia control panel (accessible from the System Tray near the clock) and find the new card. Hopefully the card should automatically be set as the dedicated physics card, but if not you can configure it as such.