Wirebook › Glossary › VRR (variable refresh rate)
What is VRR (variable refresh rate, G-Sync and FreeSync)?
In one sentence: When the screen waits for each new picture from the game and redraws right then, instead of on a fixed beat, so there is no tearing or stutter.
A little more
Games don't make pictures at a perfectly steady pace: a quiet scene might run at 70 frames a second and a busy one at 50. A screen with a fixed refresh rate can't follow that. If a new picture arrives in the middle of a redraw you see a tear across the screen, and if the game waits for the next beat instead (V-Sync), pictures sometimes get shown twice, which looks like a stutter and adds delay.
VRR turns this round: the screen waits for the game and redraws the moment each new picture is ready, as long as the rate stays inside the screen's range (for example 48 to 144 Hz). FreeSync is AMD's name for it, G-Sync is Nvidia's, and consoles and TVs use HDMI 2.1 VRR. It makes uneven frame rates look smooth without tearing, and adds almost no lag.
See it in action
- BonusWhy does a game judder when it can't keep up?A screen is a flip book with a thumb that turns the page on a steady beat, and the game is an artist drawing the pages.9 min · interactive
- BonusHow does a game controller talk to a console?Your controller fires tiny paper darts at the console hundreds of times a second, each one a snapshot of every button and stick.8 min · interactive
Do it for real
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