http://www.geforce.com/News/articles/how-to-unlock-rages-high-resolution-textures-with-a-few-simple-tweaks

[img]http://www.geforce.com/Active/en_US/shared/images/articles/ragetexturetweak/RageComparison-Animated.gif[/img]

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It really made a difference for me, but I had to force V-sync and tripple buffering in the Nvidia control panel to improve the performance with the 8K textures.

So, that's the fix for me in case you have performance issues when you enable the 8K textures.

I've tried the 16K ones but everything just turns blue.