2 Replies Latest reply on Mar 2, 2017 2:56 PM by glen_s

    New PC, 6 core processor and 8GB AMD rx480, still getting video playback lag

    glen_s

      I do a lot of video editing, and with 4K video making up a lot of my content now I decided to get a new workstation as my 2009 Dell was struggling bad enough with 60fps 1080p video and I didn't think it was worth it to try and upgrade it to handle 4K content.

       

      I ended up buying this model for a new PC, which has an AMD rx480 8GB graphics card - I thought this unit would have horsepower to spare when it comes to playing 4K video etc.,  I also bought at the same time a Samsung 500GB SSD and moved the OS over to it before I installed any programs.

       

      Trouble is it isn't handling video a whole lot better than my old Dell. Yes it's better, but not by the magnitude I expected, especially with a 6 core processor, 16GB ram and 8GB video card, and an SSD for the OS.

       

      I am rendering 4K videos with Davinci Resolve, and it's still stuttering badly when I try to playback some rendered files. It doesn't seem to matter if I use VLC, WMP, Windows 10 "film & tv" player or quicktime. Video will just stop, while the slider keeps moving, then after a couple of seconds start playing again. I notice the CPU is barely working while this is happening, and given that video playback is (supposed to be) CPU intensive I'm wondering why this is.

       

      In fact I just colour graded some 1080 60fps video and with some short 30 second clips I am even getting bad hangs & judder in the playback.

       

      I've already implemented a lot of the "tweaks" like turning off a lot of the windows 10 stuff and creating a single swap file etc.

       

      Given the huge jump in processing power and graphics card capability this new computer has over my old one - why can't I playback ALL video smoothly - and what can I do about it?

       

      Are there tweaks to the GPU I can make that might help?

       

      thanks in advance!

        • Re: New PC, 6 core processor and 8GB AMD rx480, still getting video playback lag

          Hello glen_s,

           

          I am very interested in your problem, or the problem of your new PC exactly.  Would you please first check Davinci Resolve working normally? Or in other words, use other PC to playback the 4K video file, will it playback normally on other PC? What kind of players are you using to playback 4k video? Does it utilise the GPGPU to accelerate or you have choose the proper output method? Is the GPU driver installed correctly?

           

          Oh, sorry, what does "It doesn't seem to matter if I use VLC, WMP, Windows 10 "film & tv" player or quicktime" mean? Those players would play 4k video without problems?

            • Re: New PC, 6 core processor and 8GB AMD rx480, still getting video playback lag
              glen_s

              Thanks for the reply

               

              I don't know if Davinci Resolve uses the GPU directly to help process/accelerate the video or not while processing, but I think it might by default because it would not even work with my old PC with a 1GB card.  I also use Sony Vegas for editing and it has an option to use GPU while rendering but I usually turn it off because it does not help a lot.

               

              When I said "It doesn't seem to matter if I use VLC, WMP, Windows 10 "film & tv" player or quicktime" I meant that all of them will sometimes stutter or lag while trying to playback video. I have not had a chance to try the videos on another PC yet.  The funny thing is it is not all the time this happens - sometimes I can play video smoothly, and sometimes it will lag badly, even 1080-60p video.

               

              There is one clip in particular that seems to be giving me issues this week, so I am going to copy it to a USB and try it on my work computer, and HP which is not near as powerful as my home workstation.

               

              I keep the drivers updated whenever a new update comes out from AMD. I am still puzzled why the CPU does not work harder when playing video, since this is a CPU intensive task.