GTX 980 Review - Sim Racers Perspective

Discussion in 'General Discussion' started by Seahawks1Fan, Dec 9, 2014.

  1. DrR1pper

    DrR1pper Registered

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    60hz vs 120hz isn't technically more input lag inducing but when you pair it with vsync it does imho.

    So, 60hz refreshes every 16.7mhz and 120hz every 8.3ms. With vsync enabled, there is a frame buffer so frames can be sent in sync with the displays refresh. Since the frame durations are twice as long on 60hz vs 120hz, the accumulative frame buffer lag from vsync is twice as long (regardless of how many frames are buffered in the vsync used).

    When i made those videos, i did some more tests in my own time and found vsync at 120hz for competitive gameplay was a perfectly reasonable compromise between (barely any) input lag vs the benefit of no screen tearing and frame smoothness. At 60hz's the input lag was noticeable. However i had never checked before then and was non the wiser until i had purchased a 120hz monitor and done a comparison (with the same display) for myself.

    I use adapted vsync in rf2, best compromise for when the fps does dip below 120fps from time to time.
     
  2. Ari Antero

    Ari Antero Registered

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    Really?

    FPS = Frames per second
    Hz = Cycles per second.

    FPS and Hz are basically the same thing, In this case they both mean screen updates per second.

    The optimum ratio is 1:1, The graphics card sends one frame and that get displayed on screen, then sends a another frame etc. If you have a 120fps and a refresh rate of 60hz, it simply can't display all 120fps. It either drops 60 frames, or combines 1 and half frames and displays it as one frame. Both will result in screen tearing which is pretty annoying.
     
  3. oHOWEo

    oHOWEo Registered

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    The lag from vsync is caused by the driver/software telling the game engine "stop what your doing, the display isn't ready for you yet"
    Naturally vsync at 120hz will incur less lag than 60hz.
    MSAA also creates input lag which I can definitely detect in bf4.
    What I dont fully understand is the amount of input lag, it varies from software to software. The way vsync creates lag you would think that the faster or higher percentage over the displays refresh rate then the lag would increase, this doesn't seem to be the case. For example on a 60hz screen you would think if you turned the candy up (not aa as that causes lag too) and your fps maxed out at 65 naturally then you would think capping it at 60hz for the display would create only minimal lag?

    I've been pc gaming for over 10years now and up until say 12 months ago, I was blissfully unaware of vsync lag and also aa lag, so I had a lovely image, no tearing and was non the wiser, how a little knowledge sucks!
     
  4. DrR1pper

    DrR1pper Registered

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    hmm...i don't see what i wrote being in conflict with what you're saying. The only condition i maybe should have said earlier in my post was vsync with fps not dipping below the cut off point (i.e. fps is always above 120fps with vsync 120hz and fps is always above 60fps with vsync 60hz). At the end i mention i use adaptive vsync which is a way to get vsync 120fps/hz without it suddenly dropping to vsync 60fps/hz (which would then become a significant input lag problem) if the game fps drops below 120fps.
     
  5. Spinelli

    Spinelli Banned

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    I feel sorry for anyone's driving if using VSync, even @ 144 fps/Hz
     
  6. DrR1pper

    DrR1pper Registered

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    Why is that?
     
  7. adaptable1

    adaptable1 Registered

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    Once you see it... you cannot un-see it! Just 4 months ago, I played at 60hz across 3 monitors, none the wiser... now that I have 3 x 120hz monitors, I notice all the rendering imperfections & choppiness if I play at a lower settings. 120hz is just so addictively smooth. Without vsync, the tearing/stuttering is noticeable. At 120hz with vsync, everything is smooth, and I'm winning races that I previously sucked at, particularly online.
     
  8. stonec

    stonec Registered

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    Because VSync buffers frames, it doesn't allow your graphics card to output a frame when it's ready, it rather has to wait for the monitor to be in sync. Bigger buffer = more input lag.
     
  9. DrR1pper

    DrR1pper Registered

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    Yes but have you tried 120hz with adaptive vsync? There will ofc still be some amount of input lag but it's near imperceivable (at least) to me whereas 60hz vsync is perceivable. And when i mean it's near imperceivable @ 120hz, i'm making that observation in a scenario where input lag is most noticeable...by oscillating the wheel quickly and repeatedly as shown in my second video posted by Ari.




    The smoothness and tear-free nature of adaptive vsync @ 120hz is sublime.
     
    Last edited by a moderator: Dec 14, 2014
  10. oHOWEo

    oHOWEo Registered

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    I disabled v-sync in all my quick reaction games, The screen tearing doesn't even catch my attention any more although for some reason I don't get a great deal of it which I'm equally puzzled and happy by!
     
  11. Spinelli

    Spinelli Banned

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    DrR1, other than possibly less noticeable stutters when/if your framerates drop, then I'm pretty sure adaptive VSync is identical to regular VSync.

    I gotta do another test, but I'm pretty sure the input-lag of VSync 120 fps/Hz was noticeable compared to how instant non-VSync felt

    Setting pre-rendered frames to 1 gives a noticeable improvement to VSync, but from what I remember, it still didn't compare to non-VSync, let alone non-VSync w/ pre-rendered frames @ 1.
     
  12. DrR1pper

    DrR1pper Registered

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    Yes, they are identically the same so long as the fps stays above the display refresh rate. Adaptive vsync is the same as normal vsync with the exception that it automatically disables vsync when the fps goes below the refresh rate. That way you don't suddenly get 60fps vsync if the actual fps falls between 60-119fps in game. Perhaps i didn't explain myself clearly.

    Don't forget that if you're going to test "normal" vsync @ 120hz then you have to make sure gameplay remains above 120fps at all times. The alternative is to use adaptive vsync.
     
  13. Spinelli

    Spinelli Banned

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    Yup, of course :)
     
  14. Ari Antero

    Ari Antero Registered

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    :rolleyes:
     

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