Slow Internet connections, corrupt video software and browser settings can all cause streaming video to stutter. If online videos are unwatchable due to lag, and the stutter occurs on more than one website, checking your computer's hardware, software and network situation can help you to pinpoint the source of the video interference. In some cases, the problem isn't related to the computer, but rather due to a bandwidth cap caused by your Internet Service Provider.
Exit from all other programs using the Internet or CPU. Click the arrow icon, found on the far right of the taskbar, to see all hidden programs.
Right-click each program, then select "Exit" or "Close" from the context menu.
Disconnect all other computers from the Internet or exit from all peer-to-peer applications running on other PCs.
Check the video streaming. If the stuttering continues, click "Start." Go to "Control Panel." Click "Hardware and Sound," then go to "Device Manager."
Expand "Display Adapters." Double-click the video driver, then check the "Device Status" field for errors. Look up the error code on Microsoft Support for instructions on how to resolve the issue, if applicable.
Click the "Driver" tab. Click "Update Driver" to check for new video software. If the wizard detects an update, follow the onscreen directions to upgrade the driver. Otherwise, close the wizard. Click "Uninstall" instead.
Restart the computer. Follow the same directions as above to exit from all inactive applications.
Test the video in another browser. If the stuttering doesn't occur in the other Web browser, reinstall the original browser or revert its settings to default. If the stuttering persists, go to SpeedTest.net.
Click "Begin Test" to determine the speed of your download and upload rate. If your download rate is less than 1 Mbps, contact your ISP to either upgrade your plan or figure out what is slowing down your Internet speeds.