I'm optimizing a directx graphics application to take advantage of nVidia's SLI technology.  I'm currently investigating some of the techniques mentioned in their 'Best Practices' web page, but wanted to know what advice/experience any of you have had with this?  
Thanks!
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            I'm looking at buying a new gaming PC on which to do some XNA development.  Before I buy a machine with SLI graphic cards, does anyone know if XNA has any problems taking advantage of a SLI setup?
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            For NVIDIA graphics cards, you can have two working as one (SLI). For a .NET desktop application, I need to be able to check that SLI is enabled. Is this possible?
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