Question about 30Hz refresh rate and gameplay framerate

Discussion in '3D Hardware, Software & Output Devices' started by Flux, Sep 5, 2013.

  1. Flux

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    Can you have a game running at 60Hz(gameplay framerate) yet have the vga refresh at 30Hz?

    Is that possible?
     
  2. Silent_Buddha

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    Yes, if your display is limited to 30 Hz then just turn off Vsync.

    It's the same thing as having a 60 Hz LCD but benchmarking or playing a game at over 100 FPS.

    Regards,
    SB
     
  3. Davros

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    You have a 30hz monitor ?
     
  4. lanek

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    If we are speaking about the same thing.. you can even fix a limit on the fps to 60 ( 60hz), ( using radeon Pro or NvInspector ).

    Anyway, at 60fps on 30hz monitor, you will get the same result of running a game at 120fps on a 60hz monitor without v-sync, screen tearing.
     
    #4 lanek, Sep 5, 2013
    Last edited by a moderator: Sep 5, 2013
  5. Flux

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    So if a game running at 60Hz internally and the VGA refreshes at 30Hz(within a 60Hz interval) will there be 1 frame of delay between frames?
     
  6. Rodéric

    Rodéric a.k.a. Ingenu
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    Not sure what you mean, if you're rendering at 60Hz but displaying at 30Hz, you're only seeing half the frames.
    There will be no delay, you just see the 2nd, 4th, 6th... frames.
     
  7. lanek

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    Oh, i think i start to understand what you mean, in your case it is not 60fps you want but simulate a 60hz output on the vga on a 30hz monitor /TV )..

    60hz = 60fps... but in your case you will just want use no "v-sync", so no link between frame / second and sync. ..

    Just set v-sync to off in your driver / game, and let it run as it is.. your framerate will just be what your gpu is able to do.. driver and games will still display 30hz as the only option available but it will not be enabled ( as v-sync is off )

    Now if you experience to much screen tearing, you can use a fps limiter and so fix it at the level you want ( max fps ).. so 40-60fps etc .. ( basically, like this you simulate a output at 60hz/60fps, as the max framerate and min if you have enough gpu power are fixed to 60fps ( basically the same is doing the v-sync )
     
    #7 lanek, Sep 6, 2013
    Last edited by a moderator: Sep 6, 2013
  8. Davros

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    Are there even monitors that have a 30hz refresh?
     
  9. lanek

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    For monitor, i dont think, but first 4K TV and some "standard TV" who dont have the 50-60hz setting for the "PC HDMI " input .
     
  10. Silent_Buddha

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    Yes, any HDMI 1.4 based 4K TV won't be able to support 4k at higher than 30 Hz due to the limited bandwidth of HDMI 1.4. And any HDMI 2.0 based 4K TV won't support anything higher than 30 Hz on video cards that don't have HDMI 2.0.

    Regards,
    SB
     
  11. Blazkowicz

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    4K 30Hz monitors are available and affordable, it's the well known 50" Seiki TV. I've seen there's a cheaper 39" now.

    http://www.dslrfilmnoob.com/2013/07/22/seiki-4k-monitor-price-drop-39-inch-4k-model-1000/

    So, $1100 for the 50" and $700 for the 39"!
    So you have to make do with 30Hz, if you want to be an early adopter. Having such a monitor for work must be incredible, if you need to see a lot of code, text, plans, stuff. That beats trying to read a two-column PDF on a 1366x768 display lol.

    But for gaming I think you'll have to live with it or try playing at 1920x1080 60Hz instead. Don't expect to play Counterstrike at 4k and not get your ass handed over, at 30Hz.
    It's conceivable to run the game at 60Hz vsync'ed and drop every other frame, that will give you better keyb/mouse input, but I think there's no way to do that unless AMD or nvidia write it into their driver.

    Game capped to 60fps (you can sometimes do that in the game's console) and vsync off, you can try that but there's no guarantee you won't get tearing. Worst case you get perfectly timed tearing in the middle of a frame, every time.
     
    #11 Blazkowicz, Sep 8, 2013
    Last edited by a moderator: Sep 8, 2013
  12. AnarchX

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    These 39" 4K TV panels seem to allow some overclocking to 40-45Hz input: http://www.overclock.net/products/skyworth-39e780u-uhd-tv/reviews/6071#

    And if you start to use interpolation there are some options between 2K and 4K:
    By 2014 we might see them close to $500: http://www.digitimes.com/news/a20130227PD211.html
     
  13. Davros

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    What i wonder is how will normal hd games look when stretched to 4k?
    i tried to fake the effect using my eyefinity setup and some games looked ok (deusex 1) some games looked bad (metro 2033)
     
  14. Flux

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    Thank you all very much.

    Your a lot of help and I am learning a lot from you guys.

    Cool!
     
  15. Silent_Buddha

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    Assuming a good scaler, then it shouldn't look too bad. The pixel density will be high enough that it would be a rare individual that is able to distinguish individual pixels. So any slight blurring will likely be below the visible threshold for most people, unlike what happens with current monitors and the relatively low pixel density that they have. So for most people, I'd imagine they would not be able to distinguish a native 1920x1080 image on a 24" current gen monitor and 1920x1080 upscaled on a theoretical 24" 3840x2160 monitor.

    Regards,
    SB
     
  16. Davros

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    It was a chain link fence in metro 2033 that stood out as particularly bad
     
  17. kalelovil

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    In the case of a simple doubling of vertical and horizontal pixels like that from 1920x1080 - 3840x2160 shouldn't the image appear exactly the same?
     
  18. Silent_Buddha

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    If there is no upscale filter, then most likely. If there is a good upscale filter, there's actually a possibility of the upscaled to 4k video looking better than the original for lines with high contrast. A form of AA if you will.

    Regards,
    SB
     
  19. Blazkowicz

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    There's a novelty with 4K displays : vertical tearing :eek:
    http://www.hardware.fr/news/13358/nvidia-ama-liore-jeu-4k-avec-pilotes-327-23.html
    The above article (in French) talks of it, but it foremost announces a nvidia driver that fixes it and is immediately available, so it's not too much a big deal. AMD driver will come a bit later (they say next week AMD will talk about the next Radeons, unsure if only next-gen Radeon will be vertical tearing free or current gen too). What is tricky is fixing it with vsync off.

    Ah well, that's off-topic I guess, it is 4K 60Hz displays, presented as two 1920x2160 displays, that can have this stuff happening. 30Hz 4K displays are a single surface beamed over HDMI I think.
    But it's a funny issue, and refresh related.
     
  20. Davros

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    that looks like bezel compensation is still active
     
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