ELMB (Extreme Low Motion Blur) is Asus’ proprietary technology made to reduce eye tracking motion blur. It is a form of backlight strobing technology, made to eliminate any blur on the display by turning off the backlight of the monitor in between refreshes. Note that this technology can only be used at fixed framerates, such as 85Hz, 100Hz, 120Hz.
Modern displays, due to the way their technology works, suffer from ‘sample-and-hold’, meaning that frames are displayed until the frame refreshes again, i.e. the image is always ‘on’. Each pixel (which is what the image on the screen is made out of) takes a while to change in brightness and color though, even on monitors with the fastest response times possible. When fast moving objects move around the screen this can cause eye tracking motion blur, since the display cannot respond fast enough to accurately display the objects’ travel line.
Our eyes are tracking the fast moving object so fast that our eyes will be at a different position at the start of a frame vs. at the end of a frame. This causes what we know to be ‘eye tracking motion blur’.
The only way to combat eye tracking motion blur is by shortening the amount of time each frame is on screen. That’s done by (for example) producing higher refesh rate monitors, but also by what we call ‘backlight strobing’, i.e. turning the backlight off in between frame refreshes, thus shortening the amount of time that a frame is displayed even more.
ELMB is Asus’s own backlight strobing technology. Provided your PC can reliably output enough frames to match the rate at which ELMB is working it will greatly reduce the blur on the screen with minimal side effects. Not much info is provided on this technology by ASUS, but ELMB does work the way it’s advertised and essentially eliminates any motion blur, which can greatly improve ingame performance in fast paced games.