[TIPS] How to Enable SLI and CrossFire Support for OpenGL Applications

Enabling SLI Enabling SLI

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SLI / CrossFire Article Index

FurMark, FluidMark, TessMark and ShaderToyMark are all OpenGL applications. Unless the OpenGL application is a commercial video game, you have to tweak a bit to make it CrossFire or SLI compliant. Here are some tricks you can apply to take advantage of the multi-GPU support in FurMark or in any other OpenGL application.

1 – Common rule: FULLSCREEN

To take advantage of SLI or CrossFire, you have to run the OpenGL application in FULLSCREEN. Both SLI and CrossFire only work in fullscreen. Currently there’s no way to get SLI / CF system running in windowed mode… with gaming hardware (GeForce or Radeon based cards). I recently discoverd that you can do multi-GPU in a windowed application with CrossFire PRO (FirePro graphics cards).

2 – How to enable SLI support

SLI is NVIDIA multi-GPU technology. Thanks to SLI you can use several GeForce graphics cards at the same time to speed up the 3D rendering. There are several ways to enable SLI with an OpenGL application like FurMark:

2.1 – first thing, be sure that SLI is enabled. Just select Maximize 3D performance in NVIDIA control panel (or NVCPL):

Enabling SLI

2.2 – The application has a SLI profile provided by NVIDIA (like popular OpenGL video games: Quake Wars, Wolfeinsten, etc.): you have nothing to do. Just start your application in fullscreen, that’s all.

2.3 – The application does not have a SLI profile like FurMark. In that case try the following tricks:

2.3.1 – The correct way: enabling SLI in NVCPL is not enough. You have also to manually set the SLI rendering mode to AFR1 (Alternate Frame Rendering 1) in NVCPL (Manage 3D Settings entry on the left):

SLI rendering mode: AFR1 (Alternate Frame Rendering 1)

This setting is enough for FurMark. And to be sure your SLI cards are working together, you can enable the SLI Visual Indicator:

SLI Visual Indicator

Once your SLI is okay, start a FurMark test in fullscreen and you should have something like this:

FurMark and a SLI of GTX 480

FurMark and a SLI of GTX 480
FurMark 1.9.0 loves SLI

FurMark and a SLI of GTX 480
FurMark 1.9.0 loves also the 3-way SLI

2.3.2 – The dirty way: the file renaming trick (part 1): renaming FurMark.exe in etqw.exe is a simple solution to make SLI working. etqw.exe is the Enemy Territory Quake Wars game and it’s an OpenGL game. Then renaming FurMark.exe in etqw.exe will allow FurMark to use etqw SLI profile.

2.3.3 – The file renaming trick (part 2): etqw does not work? Then try to rename FurMark.exe in SeriousSam.exe. Serious Sam is also an OpenGL video game and has a SLI profile.

2.3.4 – do you have another trick? Post a comment to share it.

Next page: how to enable CrossFire support.

SLI / CrossFire Article Index