Is this a video card problem?

When I watch a DVD or when I use Windows Media player to watch MPEG4 or AVI videos. the screen sometimes will black out. The sound, during the black screen sounds similar to a buzzing sound.



I upgrade the video card a while back, but somehow it still has this problem. What is causing this?|||Since there is an audio issue, it is not just the video.



If it was a serious upgrade to the video, you may need a larger power supply.



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