My laptop turns on, but I see no video?
This issue can be pinpointed to two separate items very quickly.
If your laptop will display a video on an external monitor, then you have a hardware issue with either your inverter or your backlight.
You can change the CCFL, which is referred to as the backlight, by disassembling your LCD screen and clipping the AC contact wires that are white and pink. New CCFL bulbs have to be soldered in after clipping. I get asked if inline butt splices will be crimped in and applied instead of soldering. With each system having different clearances, I see that as highly unlikely.
To change an inverter bar, you simply match model numbers and unplug a molex connector.
If it will not display externally, then your issue is geared more towards a BGA onboard issue. HP DV2000, DV6000, DV9000, TX1000, Dell D620, D630, D630, D820, D830 systems with Nvidia chipsets have the known BGA issues that I can fix.
Most systems need a double or triple chipset reflow.
If you are experiencing this issue and need an answer to why it happens or more detailed information on the issue: