Re: No video on E6420 screen prior to Windows 7 loading.
Please run the LCD BIST on the laptop to check if there is any problem with the LCD screen.
To initiate LCD BIST:
- Connect the AC adapter to your computer.
- Hold the letter <D> on your keyboard and then turn on your computer.
You will see four colors (grey, red, green, and blue) on the screen in a sequence.
If you see any colors on the screen the LCD screen is fine. If not the problem is with the LCD screen and LCD needs to be replaced.
As per the description the POST screen behavior looks normal in your laptop, the Dell screen will be available only for 3-5 seconds during POST.
Please reply with results.