Test the headphones — If available, test the headphones on another computer to ensure their functionality.Check the headphone cable connection — Ensure that the headphone cable is securely inserted into the headphone connector. See the Setup and QuickReference Guide for your computer at support.dell.com.Adjust the Windows volume control — Click or double-click the speaker icon in the lower-right corner of your screen. Ensure that the volume is turned up andthat the sound is not muted.Video and Display ProblemsCheck the diagnostic lights —See Diagnostic Lights.Check the display settings —See the Dell™ Technology Guide on your computer or at support.dell.com.Adjust the Windows display settings —Windows XP:1. Click Start® Control Panel® Appearance and Themes.2. Click the area you want to change or click the Display icon.3. Try different settings for Color quality and Screen resolution.Windows Vista:1. Click Start ® Control Panel® Hardware and Sound® Personalization® Display Settings.2. Adjust Resolution and Colors settings, as needed.Only part of the display is readableConnect an external monitor —1. Shut down your computer and connect an external monitor to the computer.2. Turn on the computer and the monitor and adjust the monitor brightness and contrast controls.If the external monitor works, the computer display or video controller may be defective. Contact Dell Support.Dell Technical Update ServiceThe Dell Technical Update service provides proactive e-mail notification of software and hardware updates for your computer. The service is free and can becustomized for content, format, and how frequently you receive notifications.To enroll for the Dell Technical Update service, go to support.dell.com.CAUTION: Before working inside your computer, read the safety information that shipped with your computer. For additional safety bestpractices information, see the Regulatory Compliance Homepage on www.dell.com at: www.dell.com/regulatory_compliance.NOTICE: If your computer came with a PCI graphics card installed, removal of the card is not necessary when installing additional graphicscards; however, the card is required for troubleshooting purposes. If you remove the card, store it in a safe and secure location. For informationabout your graphics card, go to support.dell.com.