|Telling us it's a PC doesn't tell us whether it's a desktop or laptop computer. |
If the subject computer is a HP Dv2422ca it's a laptop.
Having no video on a laptop's built in display is very common, after the laptop has been used a lot, or at any time if it's been dropped or had liquid spilled on it, or if your battery or charging system isn't working properly.
Since it last worked properly...
- have you dropped this laptop, or have you spilled liquid on it ?
- have you re-loaded Windows from scratch from a regular Windows CD ?
- have you just installed video drivers ?
How old is this laptop?
If it's over two years old, how long has it been since you changed it's main battery ?
Laptop no video (or video problems), and battery, AC adapter, power jack T shooting.
See response 1:
DO NOT plug in or unplug a monitor's video cable into / from a video port while the computer is running. Doing so can damage the monitor's circuits and/or the video adapter's circuits.
Some laptops will display on an external monitor without you having to do anything.
If you get no video on an external monitor, some laptops have a key combo that you must press to toggle the display to external video only / sometimes both / built in display video only - see the Owner's or User's manual for the model.