Jerky HD video streaming

I have a decent PC with i5 3.4 GHZ processor with 8 GB ram, Win 7-64 bit. My screen res is set to the highest 1680 x 1050. Color depth is at highest 32 bit. And the refresh rate is 60 HZ.

Why when I am viewing HD video on youtube and other internet streaming does the video seem a bit jerky at times ? This is nothing to do with the download speed.

Does the type of motion make a difference? Meaning do you see it mostly in camera pans or does it happen on everything?

Not too sure but I think it might be camera pans.

You will often see this if your monitor and material are not using the same frequency/frame rate. For example if I look at material that I've created at 23.98, 24 or 25 fps on my monitor the pans or will look jerky in real time because the monitor sync is at 60Hz. If you step through the footage it is smooth. I generally do not see this if I'm looking at 29.97 material.

Also, I find I get different results in different players. I really like VLC. I always check my clips in VLC and QT.

one way to dramatically improve performance for playing video is to use SSD drives instead of standard drives.

Perhaps even high shutter speed of that video makes jerky effect.

SSD's are not always the best option for video.

the I5 processor is a little slow but Jerky video is almost always a slow video card issue.
Maybe time to upgrade the card.

What card do you have?

Nvidia GeForce 9500 GT

Just make sure your power supply can handle any card you decide to use. Also if you need a larger wattage supply that it will fit in the computer case.