To use PhysX GPU acceleration on SLI-ready systems

Note: To use this procedure, your system must be PhysX-capable and have more than one GPU capable of running in SLI mode. The GPUs must also be selected for CUDA (see the CUDA-GPUs setting on the Manage 3D Settings page).

From the NVIDIA Control Panel navigation tree pane, under 3D Settings, select Set SLI and PhysX configuration to open the associated page.
In the PhysX settings section, click the Processor list and then select the NVIDIA GPU to use for PhysX acceleration.
- Choosing "auto-select" lets the NVIDIA driver use the best processor for PhysX.
- If you want to use your selected GPU only for PhysX and not for SLI rendering, click the Dedicate to PhysX check box.
The GPU configuration visualizer shows the pending PhysX configuration as well as the display connections and enabled state of the displays. The PhysX cloud indicates that all the active displays benefit from PhysX, and points to the GPU that will be used for PhysX processing. If there is no pointer, then the CPU has been selected for PhysX processing.
Select an SLI configuration.

Under SLI configuration, click
- Maximize 3D performance to enable SLI rendering where possible for maximum 3D performance.
- Activate all displays to enable all available displays. If possible, SLI rendering may still be enabled.
- Disable SLI to disable SLI rendering, for example, if you encounter compatibility issues with your 3D program.
The GPU configuration visualizer shows the pending SLI configuration as well as the display connections and enabled state of the displays. The SLI bar indicates the SLI mode (SLI, 3-way SLI, Quad SLI, or 4-way SLI) and points to the GPUs that are used for SLI.

NOTE: If you dedicated a GPU to PhysX, the setting could be removed if you changed the SLI configuration.
Click Apply.

If you have more than one display connected and SLI mode is enabled,

Windows XP or pre-GeForce 8 series GPUs

You can select which display to use to view your game. Use the Set up multiple displays page to select which SLI display to use as the primary display. The GPU connected to this display will function as the "primary" GPU, all others will function as slaves to the primary GPU.

If none of the displays in the SLI group are the primary display, then the driver will select which display to use to view SLI accelerated games.

Windows Vista or later, and GeForce 8+ series GPUs

You can select which display to use as the SLI focus display (the display to which you want to apply full SLI acceleration for full-screen applications). Use the Set up multiple displays page to select which SLI display to use as the primary display. This becomes the SLI focus display.

If none of the displays in the SLI group are the primary display, then the driver will select which display to use as the SLI focus display.