It sounds like the video driver is not installed. Have you checked to see if the actual nvidia or ATI video driver is installed. Windows will install a default driver that will allow you to use the laptop but will not work very good.
Go to your device manager ( control panel >> system)
under video adapter it should NOT say "standard video adapter". If it does you will need to download and install the driver from Dells website. Here is a link to download the drivers: http://support.dell.com/support/downloads/driverslist.aspx?c=us&l=en&s=gen&os=WW1&osl=en&catid=&impid=&SystemID=INS_PNT_P4_8200
If you need parts for your laptop. These guys are the best.
http://www.parts-people.com/index.php?action=category&id=141&subid=70
Hope I helped
I have a Dell Inspiron 8200 in which the operating system went down a few months ago and was recently fully repaired. Everything works fine with the computer except when I go to view video (youtube, etc.) the video lags heavily and does not stream, meaning it basically shows a different still image every 3 seconds. Also when typing in chat conversations the type also lags. There is no problem with my internet connection and my suspicion of spyware was negative. Any help is greatly appreciated

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