> 1/144sec frame transmission to monitor = 6.9ms (G-SYNC) > > Well, if this is how the thing actually works, then this technology is pure smoke. I > thought the monitor would really show the frame as soon as it's signaled by the video > card, at any arbitrary rate (between a range). If it's simply 6.9ms granular then
Not granular. You can have any intervals between frames, as long as it's >= 1/144sec (6.9ms).
The point I am making is... All monitors, running at 60Hz, have ALWAYS taken 1/60sec (= 16.7ms) to transmit the frame to the display. CRT, LCD, DLP, plasma. Even your 120Hz monitor configured to 60Hz mode. See high speed video. Top-to-bottom scan. High speed video of CRT: http://www.youtube.com/watch?v=zVS6QewZsi4 High speed video of LCD: http://www.youtube.com/watch?v=nCHgmCxGEzY
Observe how all of them take 1/60sec to "paint" the image from top the bottom? Exactly. Frames have never been delivered "instantaneously" all at once to the displays. Never has been before. For over 75 years, back to the first televisions, we've always had finite speed delivery of images to the screen. Yes, it's dissapointing.
So you see, G-SYNC revolutionizes frame transmission times, by decoupling the scantime from the refresh rate. Instead of 60Hz frames taking 1/60sec to scan top-to-bottom. You get 60Hz frames taking 1/144sec to scan top-to-bottom. Frame delivery times are revolutionized by G-SYNC. Someday, we might even have instantaneous frame delivery times (Direct3D Present() instantaneously shows whole image to your human eye balls, in 0ms) -- we're not there yet -- but reduction of 16.7ms scanout at 60Hz on all 60Hz displays in history, is greatly reduced to a mere 6.9ms scanout at 60Hz on G-SYNC.
Instead of scanout being dependant on refresh rate (e.g. 60Hz having 1/60sec scanout, 85Hz having 1/85sec scanout, 100hz having 1/100sec scanout), all refresh rates (50Hz, 60Hz, 100hz, whatever), now all have 1/144sec scanout! That's another reason makes G-SYNC so revolutionary for emulators, from an input lag perspective!
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The faster frame delivery time is another advantage in addition to the variable refresh rate. So, yes, it is already what you thought it was earlier, but *even* better.
For emulators: (1) G-SYNC advantage #1: variable refresh rates controlled by Direct3D Present(). 50Hz, 53Hz, 60Hz, 60.1Hz is easy. Zero speedups/slowdowns. (2) G-SYNC advantage #2: faster frame delivery/scanout. 60Hz frames delivered to monitor faster over the cable, and painted onscreen, than any past display running 60Hz. (3) G-SYNC advantage #3: stutter elimination (16.8ms won't cause you to miss VSYNC, it'll refresh right away)
Edited by Blur Busters (10/25/13 09:08 PM)
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