If I'm using higher resolution in games using vsr at 4k, 5k ect, it can be be demanding depending on the game. The likes of oldies like half life 2, f.e.a.r, far cry 2 with vsr at 7k maxed out graphic settings I was still pulling 80+ FPS, but mostly over 100 FPS and the game looks amazing.
But when it comes to setting the desktop to 7k using vsr and then going back to my native 1440p resolution in games there's zero performance loss, I get the same performance as I would normally at 1440p. And as you've seen with they pictures, there's a clear difference having the desktop at 7k vsr and just using your native resolution in game.
Ill need to take a few more screenshots in other games, and update this post with a few more comparisons. I was taking the screenshot at native 1440p, then changing the desktop Res to 7k and running the game at 1440p. As soon as I changed the desktop at 7k and jumped in to breakpoint i was like this looks so much better than before, I thought I had maybe changed the Res to 4k but when I saw I was still at 1440p I was like this can't be right lol.
I know the likes of VSR and DSR they use some kind of AA which probably explains why there less jaggies when using desktop vsr and native in game, but as for the textures and other details being much clearer and sharper that's what boggles my mind. Having had experience with DSR for years I can say vsr is by far superior imo, DSR is a blurry mess at times even when changing the settings a bit, vsr just looks amazing.
