Consider the following scenario. One of the following conditions is true:

• Your computer is running a version of Windows Vista that does not support the Windows Vista Aero theme. For example, your computer is running Windows Vista Home Basic.
• Your computer is running a version of Windows Vista that supports the Windows Vista Aero theme. However, the video hardware of the computer does not support the Windows Vista Aero theme.

You watch a video. You move the mouse pointer over an area of the video playback program that causes a tooltip to appear. For example, a tooltip appears in Windows Media Player when you move the mouse pointer over any of the following video playback controls:

• Play
• Pause
• Fast forward
• Rewind

In this scenario, the video playback performance may be reduced suddenly. Additionally, you may notice lost frames or other poor video playback performance.

Note: You notice the decrease in video playback performance only when the tooltip is present. After the tooltip disappears, video playback resumes as expected. The poor video playback performance may be more severe on computers that have slower CPU hardware.