Why is the screen blank on my Compaq laptop?

czyren November 11, 2014

I have Compaq Presario CQ41. When I turn it on, the screen is black. When I switch it on, I can hear some noise from the fan and CDROM is functioning but still it is not responding. The power button lights up. I already tried holding the power button 1-2 mins with the battery is removed from the laptop. I also tried replacing the hard disc and RAM but it still doesn’t work. What could the the problem be? It happened after I downloaded games yesterday, but I shut it down properly and the next day that black screen happened.

  1. Bruce E
    November 13, 2014 at 10:17 am

    Even if you don't have an external monitor, you need to try toggling the display. The most frequent problem I see with laptops regarding displays is that the user has inadvertently hit the key combo to switch it to an external monitor when there isn't one resulting in a black laptop display.

  2. Jan F.
    November 12, 2014 at 9:24 am

    If your screen stays black for the entire time, not even the POST (Power-on Self Test) is shown then it indicates a hardware issue.

    Do you have an external monitor or display you can connect to? Connect your external display, give the system some time to (possibly) boot and then try pressing the Fn+F4 key to toggle the display. If you get an image on the external monitor then it's an issue with the built-in LCD, maybe the cable is lose, the lid open-close-detector doesn't work, inverter, etc.
    If that doesn't work either I'm afraid it might be the graphics card or worse.

    I would suggest a professional repair service.

  3. ha14
    November 11, 2014 at 11:17 pm

    it can be graphic card problem, corrupted graphic card driver.... can you do factory recovery (this will delete all files)
    try to reset cmos battery

  4. Doc
    November 11, 2014 at 10:51 pm

    Since you don't even seem to see the BIOS screen on startup, it's likely not a driver issue, regardless of the OS you're using (Windows, Linux, Hackintosh...)
    Probable culprits are the data cable connecting the screen to the motherboard/video card worked loose or is broken, the power wires to the cold cathode tube backlight is broken or loose, or the cold cathode tube backlight is broken or burned out. You'd need to remove the bezel and the LCD unit to check the connections; I'd recommend taking the system to a reputable repair shop to do this, as there is some dangerous voltage going to a cold cathode tube.