Hi Zack,
It can help w/ improving the graphical image quality output of your 680 by telling the CPU/vid card to draw & render graphics frames at a higher resolution which can give a better looking graphical image then the GPU will then down sample the image so that it will then fit within your existing monitor's native resolution......
Now whether this can help w/ getting your 680 to perform better will depend on various factors that only you can discern, but to give 1 example of a potential performance gain:
If you're using high amounts of AA & TransAA (supersampling) at your monitor's native resolution of, say 1920x1080, these methods of smoothing the edges of graphic images require a lot of GPU rendering power to do smoothly. You can trade off some of the GPU rendering power used to apply the AA & TransAA to the same graphics frame at 1920x1080 by rendering it at a much higher resolution, say 3840x2160 (4K) using very little AA or TransAA or using none at all then have the GPU to down sample the finished 3840x2160 graphics frame back down to 1920x1080 resolution...you can get a much improved graphics image that can be displayed at your monitor's native res, takes up no more of the frame buffer as a std 1920x1080 graphics frame, rendered for less GPU power needed (here is where the graphics card performance improvement can come from) that looks much better. In short the finished graphics image will look like, walk like & smell like a fully rendered 3840x2160 image but it will fit on your 1920x1080 monitor's display area.........
But if you were already not using AA & TransAA to start with at your monitor's native resolution & you used DSR as described above you could lose more GPU performance in the process of gaining a better graphics image........................
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Does this explaination help to make sense of all this? I hope so as I'm worn out from trying to keep it as simple as I could & not mess up.
Hope this helps you out...............
