144hz monitor video lagging or stuttering problem

[RoronoaZoro777]

Hi..., I bought acer gn246hl just 2 days ago, a 144hz monitor but while watching movies on vlc player , the video kinda lags and the video doesnt run smoothly. I dont know why it is happening. Is there a special setting for watching videos on 1080p 144hz monitor smoothly? It happens the most while I am watching videos on youtube even when its fully buffered. I searched for the solution on internet but I couldnt find anything. My system specs are

i5 7600, radeon hd 5670, asus b250 prime motherboard, 16gb hyperX ram.

Please someone help me.

[Jimkirk363]

@RoronoaZoro777Your video card may struggle as its a bit dated.

[intender]

you are trying to play a lower fps source on a high refresh monitor.  you will need to set your refresh rate on the monitor to something like 60 or 120 for it to be smooth.  most videos end up at either 30 or 60 fps, and unless your videos are encoded at 24 fps then this is going to happen.  144 is not equally divisible by 30 or 60, so somewhere in there you are going to lose some frames.  thats why most high refresh rate tv's are either at 120hz or 240hz, because they can play 24fps, 30fps, or 60fps videos without looking like crap. 

 

you can also try enabling vsync and see if that helps. 

[Guest]

Hi! I hope I won't regret too much that I registered here just to answer this question.

 

@RoronoaZoro777, for starters try setting your brand spankin' new monitor to 120 Hz. If that helps, then it's possibly due to the fact that 144 factors into 2⁴*3^2, which means that the common 30 fps content is not compatible with it as 30 factorizes into 2*3*5. My mind is a bit foggy regarding integer math but what I can say for sure is that lack of 5 in 144 factorization means 30 fps content will never cleanly fit into it even with frame duplication, meaning frames will always spend varying time on screen (or you will get a progressing desync). This is called judder and is best described as "video not running smoothly", and is solved by frame interpolation for which you will need to use either madVR on Windows or mpv on Linux'n friends (at least the later requires some extra configuration, natch'). What I'm more unsure about, though, is whether you could even easily detect judder at those frame rates, especially considering that 60 fps screens have the same issue as that "common 30 fps content" I mentioned is for black and white TV signal and actual NTSC sources are using a bit lower fps to provide color signal in a backwards compatible manner.

 

Which brings us to what to do if even 120 Hz is still problematic. Basically there are three likely causes and multiple of them may be at play here. First, in terms of raw bandwidth an HD 5670 should have no trouble with just 144 24 bit FullHD frame buffers, even if they had to sent to it as rgba16 (literally twice the size of rgb8 pixel format). But it all changes if even basic frame interpolation is used, given that 120 and especially 144 fps would be close to the max fps an HD 5670 can do in a light gaming title, and even a couple of shaders being applied to each of those textures to scale or otherwise manipulate them could be the figurative straw that broke the camels back. Secondly, this assumes a 3D pipeline such as OpenGL or DirectX being in use. If VLC is using some less direct method for video presentation, then that could easily have trouble handling such high refresh rates. You can try examining CPU and, if possible, GPU load and bandwidth utilization to see if you might be hitting a bottleneck in one of those areas. Thirdly, the fact that even varying frame doubling of 30 fps content would not fit 144 Hz cleanly (due to the aforementioned lack of 5 in the factorization) coupled with the high refresh rate could be triggering bugs in either VLC or AMD driver. Therefore try using something other than VLC, as well as making sure your AMD driver is up to date. MPC-HC might be a good first alternative to try. If that helps, then you can try going back to 144 Hz, and just maybe it will work (though you will need to use frame interpolation for best results).

[RoronoaZoro777]

On ‎8‎/‎23‎/‎2018 at 1:12 AM, jimkirk363 said:

@RoronoaZoro777Your video card may struggle as its a bit dated.

Thank you very much for your answer. I am looking for a new videocard to buy. but I am struggling to find a best budget gpu which also wont bottleneck my cpu. I am down to 2 choices amd rx 580 8 gb and gtx 1060 6 gb. 

I will prefer the gtx one as it requires less power.

[RoronoaZoro777]

On ‎8‎/‎23‎/‎2018 at 3:11 AM, Guest said:

Hi! I hope I won't regret too much that I registered here just to answer this question.

 

@RoronoaZoro777, for starters try setting your brand spankin' new monitor to 120 Hz. If that helps, then it's possibly due to the fact that 144 factors into 2⁴*3^2, which means that the common 30 fps content is not compatible with it as 30 factorizes into 2*3*5. My mind is a bit foggy regarding integer math but what I can say for sure is that lack of 5 in 144 factorization means 30 fps content will never cleanly fit into it even with frame duplication, meaning frames will always spend varying time on screen (or you will get a progressing desync). This is called judder and is best described as "video not running smoothly", and is solved by frame interpolation for which you will need to use either madVR on Windows or mpv on Linux'n friends (at least the later requires some extra configuration, natch'). What I'm more unsure about, though, is whether you could even easily detect judder at those frame rates, especially considering that 60 fps screens have the same issue as that "common 30 fps content" I mentioned is for black and white TV signal and actual NTSC sources are using a bit lower fps to provide color signal in a backwards compatible manner.

 

Which brings us to what to do if even 120 Hz is still problematic. Basically there are three likely causes and multiple of them may be at play here. First, in terms of raw bandwidth an HD 5670 should have no trouble with just 144 24 bit FullHD frame buffers, even if they had to sent to it as rgba16 (literally twice the size of rgb8 pixel format). But it all changes if even basic frame interpolation is used, given that 120 and especially 144 fps would be close to the max fps an HD 5670 can do in a light gaming title, and even a couple of shaders being applied to each of those textures to scale or otherwise manipulate them could be the figurative straw that broke the camels back. Secondly, this assumes a 3D pipeline such as OpenGL or DirectX being in use. If VLC is using some less direct method for video presentation, then that could easily have trouble handling such high refresh rates. You can try examining CPU and, if possible, GPU load and bandwidth utilization to see if you might be hitting a bottleneck in one of those areas. Thirdly, the fact that even varying frame doubling of 30 fps content would not fit 144 Hz cleanly (due to the aforementioned lack of 5 in the factorization) coupled with the high refresh rate could be triggering bugs in either VLC or AMD driver. Therefore try using something other than VLC, as well as making sure your AMD driver is up to date. MPC-HC might be a good first alternative to try. If that helps, then you can try going back to 144 Hz, and just maybe it will work (though you will need to use frame interpolation for best results).

I am very grateful for your answer. Thank you for helping me. I will try everything you have posted here. Also to inform you... I have updated my gpu drivers and also tried by setting 120hz and Which display option will be better? DVI? VGA ? or HDMI ? Or combination of any 2 of them?

Thank you again 

[RoronoaZoro777]

On ‎8‎/‎23‎/‎2018 at 1:47 AM, intender said:

you are trying to play a lower fps source on a high refresh monitor.  you will need to set your refresh rate on the monitor to something like 60 or 120 for it to be smooth.  most videos end up at either 30 or 60 fps, and unless your videos are encoded at 24 fps then this is going to happen.  144 is not equally divisible by 30 or 60, so somewhere in there you are going to lose some frames.  thats why most high refresh rate tv's are either at 120hz or 240hz, because they can play 24fps, 30fps, or 60fps videos without looking like crap. 

 

you can also try enabling vsync and see if that helps. 

Thank you for your answer. I will definitely try that and revert back .

[geo3]

Are you using 2 monitors? Is the second one 60Hz? Are you on Windows 10? 

 

You may be hit by a known bug. Some people report this exact issue using 2 screens with different refresh in Windows 10.

[dcouzin]

@Guest:  There is no need explain why 30 doesn't divide into 144.  Just divide.  4.8 is not a whole number.   Perfect playability requres perfect divisibility.  But because 144 is so much greater than 30 there will be no visible judder.  First frame of the 30p video will make 5 frames at 144 Hz; 2nd frame will make 5; 3rd frame will make 5; 4th frame will make 5; 5th frame will make just 4; etc.  Six times per second, ~35 milliseconds slips to ~28 milliseconds.  I don't think this little hiccup is noticeable.  It is much, much less of a judder than people do notice when playing 24p, 25p, 48p, and 50p videos at 60 Hz. 

For your analysis of processing bottlenecks, the 5;5;5;5;4 cadence takes rather little work, hopefully by the video card, not the video player.