So a copy from another topic I posted in, incase people do a google search and wonder the same as I did:
With a 4k TV like the SOny BRavia Xbr65x850B you can actually upscale 1080p and it's pretty damn impresive.
Take a look:
http://1drv.ms/1GhZz6f
(Please note that these were taken with an iPhone, which "features" an auto exposure I can't turn off. So they may look different in color, but in real life they do not.)
THe first image is native 4k resolution. It's really clear, but suffers from small interface which is a common problem in video games without 4k scaling. THe second Image is Native 1080p without any enhancements from the TV other than edge smoothing.
The final image is 1080p use X Reality Pro to analyze the low resolutions on the screen and replace them with artificial similar textures, making things appear significantly higher in resolution. This is available on non 4k TVs as well, so if you really want a graphics update thats cheap with no performance cost, just get a good TV with upscaling features. To be honest with you, some video games look better with the fake upscaling than they do in 4k, and it works in gaming mode too so there's no increased lag.