Troubleshooting and Maintenance 
Troubleshooting Your Computer 
104 Reference Guide 
If one or more display pixels look bad 
TFT display manufacturing is a highly precise but imperfect technology, and 
manufacturers cannot produce displays that are cosmetically perfect. Most, if not all, TFT 
displays exhibit some level of cosmetic imperfection. These cosmetic imperfections may 
be visible under varying display conditions, and can appear as bright, dim, or dark spots. 
This issue is common across all vendors supplying TFT displays in their products and is 
not specific to the HP notebook display. 
HP notebook TFT displays meet or exceed all HP standards for cosmetic quality of TFT 
displays. HP does not warrant that the displays will be free of cosmetic imperfections. 
TFT displays can have a small number of cosmetic imperfections and still conform to 
HP’s cosmetic quality specifications, including the following: 
•  No more than 6 pixels remain on (always one color, such as white, red, green, or blue 
dots). 
•  No more than 6 pixels remain off (always dark). 
•  No more than a total of 8 pixels stuck on or off. 
•  No other stuck pixel within 15 mm of a stuck pixel. 
Contact HP Customer Care if you have a display quality problem and require a more 
comprehensive explanation of HP display quality—see “To contact HP for support or 
service” on page 136. We expect that over time the industry will continue to produce 
displays with fewer inherent cosmetic imperfections, and we will adjust our HP 
guidelines as these improvements are implemented.  
Docking Problems 
If a port on a dock isn’t working 
•  Check that AC power is connected to the dock. 
•  Try using the corresponding port on the computer while undocked. 
•  Make sure the computer is fully inserted into the dock. 
•  See the manual for the dock. 
If the operating system hangs when you dock or undock 
•  Your system may hang if you dock or undock your computer while you are 
suspending or resuming. Make sure your computer has completely suspended or 
resumed before you dock or undock it.