Is your laptop’s screen pixels broken up like a bad signal? You shut off and tried to restart the laptop and screen is green with pixels looking messed up like a bad TV reception on satellite TV. You can hardly see desktop icons or wallpaper.
You can try powering off the laptop and reseating the battery. Power it back on. You can also try to use the laptop without the battery and just the AC Adapter.
If there is no display with the laptop’s LCD and when you hook up to an external monitor to the VGA connection then you might want to make sure you didn’t accidentally turn down the LCD brightness. Make sure you didn’t accidentally hit a function key that would turn off the display entirely or put the laptop into a different mode ie. a sleep mode. Please check out the following troubleshooting article from HP pertaining to laptop display dim.
Does the screen look similar or the same when hooking it up to an external monitor? If you didn’t accidentally change any LCD settings then it might be a hardware issue with the laptops video card. If the computer is farily new HP/Compaq should repair or replace it with their depot service.
It sounds like to me either the LCD screen, LCD inverter board, or Video Card is malfunctioning. I usually hook up laptops directly to an external monitor to troubleshoot the quickest. Make sure when hooking up to an external monitor to use the FN function key with the correct key on the laptop keyboard to make the video display show up on the monitor and not the laptops LCD.
If the picture on the external monitor looks normal then it is a problem with your laptop LCD. If the picture on the external monitor is terrible or non existant then it is an issue with your video card or video drivers. You can check out this notebook display problems page from Compaq.
Ok great you can at least use an external monitor for now. The laptop video card is fine then. Can you follow the troubleshooting steps from the following laptop repair help article.
Your laptops video card is fine so just worry about the steps about your laptop screen. If it resembles any of sections where the lcd screen needed to be replaced then I’m afraid you need the lcd screen and or inverter replaced on your laptop. At least it works on an external monitor for now.
These tips were written for a Compaq Presario C762NR Notebook PC, but can certainly be used as a basis to troubleshoot laptop LCD problems on other brands and model notebooks and laptop computers.