If you see a dim image on the LCD screen it means you have a backlight problem.
Connect an external monitor to the laptop and power it up, if you see a clear image on an external monitor, this means your video card is OK.
Dim image and/or dark display on the laptop's LCD screen indicates a faulty LCD backlight and it could be the inverter that supplies high voltage to the CCFL lamp or it is the CCLF lamp is nearly burnt out or burnt out, most likely this is the case.
The inverter can be replaced easily but the CCLF lamp is more time consuming and requires soldering skills.
Check out www.lcdparts.net
for parts, repair service and DIY info.