Native 4K or Checkerboard "uprendered" 4k

[Peh]

Slimebeast said:

Peh said:

1080p is kind of unplayable on a 4k monitor. It looks awfully blurry.

Halflife 2 in 4k maxxed out AA

http://www.pic-upload.de/view-31674270/20160911_163611.jpg.html

close up:

http://www.pic-upload.de/view-31674283/20160911_163626.jpg.html

Halflife 2 in 1080 maxxed out AA

http://www.pic-upload.de/view-31674295/20160911_163659.jpg.html

close up:

http://www.pic-upload.de/view-31674304/20160911_163720.jpg.html

 

How can it look blurry? I understand it's blurry if the monitor upscales from 1080p to 4K (and uses an upscaling technique similar to those you linked to), but can't you prevent it from upscaling so that it remains the original sharp 1080p image?

Those pics don't work, except for one.

It's basically this :

http://www.red.com/learn/red-101/upscaled-1080P-vs-4K

I have no influence of what the monitor does with the image. I just imagine that the frame buffer in the monitor is always 4k whatever the size of the source frame is and it fills due to interpolation the missing dots.