Hello,
 
I currently own a GTX 680 and I have a few questions about the audio sync in videos when you overclock and have also an issue with stuttery playback in videos such as youtube etc. I had this issue with pretty much all the vid cards I've ever had but was wondering what was causing this.
 
1- The problem is that for some reason, audio will go out of sync on some videos when the card is overclocked. An example is in X-COM:EU . All the videos in this game plays too fast when I overclock the card using EVGA Precision X, audio will lag behind (but audio appears to be the one running at the correct speed, it's video that seems to go too fast). When looking at the OSD for FPS, I see that its varying between 28-32 fps on playback. I don't know at what FPS the video is supposed to be running at (30?) but the card wants to play it too fast. Turning off Precision X will fix the issue. As said, this is not limited to this card. I remember having this issue on quite a few games when I was overclocking so I don't know if its some sort of bug or if there is a perfectly good reason as to why this happens when overclocking so I am asking the experts here to enlighten me a little bit on the subject :-).
 
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On a side note that could somewhat be related and that is quite an annoying issue. I can very easily spot when there is stuttering in videos. Things like youtube videos will sometimes stutter quite a bit (I am not talking about a clip running at 60fps that suddenly drops at 5fps. Rather a clip at 60fps might go between 55 and 60 fps or just skip ahead a few frames). If for example you look at this video:  (btw this is gonna be a kickass game). Between 0:10 and 0:20 where you see the carrier, you see the ship passing by at a constant speed. Sometimes, this will stutter, I will see some frames skip or things like that, the whole process will not be smooth. The weired part tho is that if I restart the video a few times, I will sometimes get a perfectly smooth playback. It appears to be random. This doesn't seem to be tied with OC but I can't figure out why it is doing that. It's like the video doesn't appear to lock to the proper framerate and that it keeps trying to adjust. Could use some help with this one, never been able to figure it out!!
 
TL;DR
-Why do audio get out of sync / video plays too fast when I OC my vid card? (only happens when I OC it)
-Why do certain videos, like youtube videos have stuttering / frame skipping and that reloading the video will sometimes give me a perfectly smooth playback and other times it won't? (doesn't seem to be related with OC this time)
 
Thanks alot in advance for the help!! I hope you guys have the answer for that, I have been wondering about these issues for quite some time now!!
SV

Hi Chris,
 
Thanks for the info about OC, yeah at stock settings its fine so I'll try to make smaller increments then. The computer is perfectly stable in the sense that it doesn't crash or BSOD but I understand that the OC could still be unstable without crashing the computer. Is there some sort of ratio / big calculations that I should make to endup OC'ing at the proper speed without weired results like that? Does it have to fit with cpu clocks for perfect timings things like that? But even if the OC would be unstable, I know that I could still push it without creating artifacts or unstable computer. I am more used to ppl saying that you can OC as long as it runs fine with a stresstest soft for a few hours, but there appears to be more to it than just not having crashes at 100% gpu usage?
 
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As for the second point, yes I always run on the latest drivers and I always do full clean install when I install newer drivers, I never take the risk, always prefered a clean install (checkbox when installing the nvidia drivers where it asks you for clean install or not). As for flash, I am using chrome so chrome keeps flash updated and I also tried using FF or IE, making sure its up to date for both of them and same issue still.
 
As for different video sources, I just tried the same video on IGN which is in a different player and same issue, also went to gamespot and tried watching a random video, same issue again.
 
I don't know if you get an idea of what is happening precisely but the same stuttering happens when I am on youtube and move the mouse while playing a video to have the overlay pop back in, this usually makes a big stutter (this one might be understandable as the UI has to pop in). So what I get is a bit like that however a much smaller stutter but in rapid succession (one every second or so). Sometimes it looks as if the video pauses for a milisecond and then jumps a few frames forward to get back in sync.
 
Thanks for taking the time, I hope you can help me figure this out!

I have a gtx 1070 ftw, and I did oc it, the problem with the "unstable" co is that when I am watching youtube, the card is at like 500 mHz, so it is not the of causing the problem its the app.