So if you thought that 144 or 240Hz screens are fast think again.
A website claims that they have in their possesion a prototype 480 Hz screen!!!
The original author of the article article points out that the display is actually a 120Hz 4K panel that's capable of higher refresh rates at lower resolutions.
Getting games to run at 480Hz even at 1080p gets really challenging for the hardware that exists atm.
Source : http://www.blurbusters.com/480hz-monitor-at-blur-busters/