Full HD on a 4K monitor looks worse than on a Full-HD monitor.
This happens due to blur added by all monitors and absolute majority of TVs at any scaling ratio, though this could be avoided when enlarging by an integer number of times (e. g. 2 in case of FHD→4K).
As a result, sharpness in 3D games is decreased, white lines are gray, and pixel art is not pixel art anymore.
Each logical pixel could be displayed as a square group of integer (2×2, 3×3) number of physical pixels of the same color without mixing-in colors of adjacent pixels.
Such lossless scaling is already built into graphics drivers and removes blur regardless of monitor or TV used. But scaling via graphics card cannot help if the signal source is not a computer, but e. g. a game console.
- AMD: supported for GPUs with the GCN (2012) and newers architectures in Radeon Software 2020 (19.12.2) () for Windows 10; being implemented for Linux kernel 5.4.
- Intel: supported for Gen11 GPUs in the driver 22.214.171.12455 () for Windows 10; available since in laptops equipped with Gen11 CPUs.
- nVidia: supported with limitations for RTX and GTX 16* in the driver 436.02 () for Windows 10; incompatible with HDR, custom resolutions, DSR, 4:2:0, sharpening, and hybrid-GPU laptops.
- Linux: supported in Proton 4.11-10 (); supported with limitations in XRandR 1.5.1 () and nVidia graphics driver 384.47 (): image is cropped in many games.
- Monitors: announced for the 27″ QHD monitor EVE Spectrum expected in Q1 or Q2 .