LCD backlight is on, but nothing is displayed.

Hey everyone, my laptop (specs below) has been running great for the last few years. hell i love this machine! however i have run into a problem.

Windows device manager recognizes the graphics card. latest drivers are installed. running Windows 7.

LCD backlight turns on, however, the screen constantly stays an offwhite colour.

when i connect the laptop to a VGA monitor or to a TV through S-video, it connects and everything is displayed perfectly on the external screen. the laptop LCD is still lit up a offwhite colour.

when the laptop boots up, i cannot see the bios menu, the LCD is on, but again, it is lit an offwhite colour.

anyone know what is wrong?

 

Could be the CCFL bulb is on it's way out. These can be replaced if that's the case. However, when powering up into windows 7, you might just want to check to see if you can adjust the screen brightness - click battery icon in status bar, then adjust screen brightness.

If you can't, then it could well be the bulb. I'm also wondering if there is something wrong with the inverter board - i.e. it's not passing enough power through to the bulb?

In either case, both parts are cheap enough, the inverter board being slightly cheaper (and easier to replace). Many CCFL bulbs are very difficult to replace as it requires almost completely disassembling the display. Not sure on your model seeing that the Dell service manual does not even detail where this component is hiding: http://support.euro.dell.com/support/edocs/systems/ins6400/en/sm/display.htm#wp1022270

 

yes the LCD dims and brightens when i change the brightness.

iv played around with the laptop nough and can disassemble the whole thing (almost). put new thermal paste on the CPU and graphics card, clean out the fan etc.

thanks for the help. ill look at the inverter and bulb!

i was looking into buying a Studio 1557, but if i can fix whatever is wrong with the display ill hold off until the 32nm i7 chips