Another useful use of G-SYNC is low-latency fixed refresh rate.
Since G-SYNC has an additional
advantage of faster frame delivery times, and faster on-screen scanout time, you can get 60fps@60Hz with cable delivery of only 1/144sec, and screen scanout of only 1/144sec per refresh! (or whatever maximum bandwidth the G-SYNC monitor uses -- or even theoretical future 240Hz G-SYNC monitors using DisplayPort 2.0, which would be able to do 60fps@60Hz or firstname.lastname@example.orgHz or 187fps@187Hz, all with just 1/240th sec frame delivery / scanout latency!)
In the past, 60Hz monitors took 1/60sec to scanout (16.7ms).
High speed video of CRT: http://www.youtube.com/watch?v=zVS6QewZsi4
High speed video of LCD: http://www.youtube.com/watch?v=nCHgmCxGEzY
But with G-SYNC, delivery and scanout is decoupled from the refresh rate. You can choose to do 60fps@60Hz, with a lot less input lag than any 60Hz monitor -- even less input lag than a 60Hz CRT
, because CRT's take a finite amount of time to scan from top-to-bottom.
Also, fixed refresh rate is great for G-SYNC too, as the software completely seamlessly drives refresh rate:
- Play movies 24fps@24Hz (or 48Hz, 72Hz, 96Hz)
- Play videos 30fps@30Hz
- Play movies 48fps@48Hz
- Play television 60fps@60Hz
- Play television 59.94Hz@59.94Hz
- Play old silent films at original theater speed 18fps@18Hz (or 36Hz, 72Hz)
- Variable frame rate video files
- Future movie formats (e.g. 72fps, 96fps)
- Play mixed TV material and dynamically detect 24p, 30p, and 60p material, dynamically rate-adapt to new fixed rate (with zero mode-change flicker)
- Play emulators 60fps@60Hz with lower input lag (taking advantage of 1/144sec frame delivery times)
- You can avoid stutters even if one frame takes a bit longer to render (e.g. 16.8ms instead 1/60sec = 16.7ms) for any innocous reason such as processing, background apps or error correction, you just delay that specific refresh by an unnoticeable 0.1 second rather than be forced to wait till next refresh cycle. Makes video playback even smoother.
So it has apparently great applications for movies and home theater. Variable refresh rate capability & faster frame delivery time belongs in HDMI 3.0, in my humble opinion.
Less input lag for receivers, less input lag for sports, future game consoles (XBoxTwo, PS5), less broadcasting latency due to speeded-up frame delivery between settop box and TV, less input lag everywhere, future-proof frame rates, faster frame delivery times from one home theater device to another....Edited by Mark Rejhon - 10/25/13 at 9:12pm