Screen is blank although sound and lights are evident

It sounds like your operating system file has been corrupt. You might need to reinstall your operating system. If you have a trust worthy technician that can pull your data off of the hard drive before you reinstall the os system. Hope this helps.

this sound me lcd problem try to show some official repairer.

probebly the screen issue... you need to check your laptop with external monitor and make sure that it shows the display

try uninstalling the graphics driver and reinstall, also boot up in safe mode and see if you can see screen ok, if you can its your graphics card as in safe mode no agp drivers are engaged

It could be a hardware or a software issue

First run a hardware test on the computer, follow the steps

http://findtechhelp12.blogspot.com/2010/12/how-to-run-dell-diagnostics.html

Then if there is any part defective replace it.. Else reinstall the OS to fix the issue

http://findtechhelp12.blogspot.com/2010/11/how-to-reinstall-os-in-dell-computer.html

Possibly the monitor is defective - usually most laptops have a blue plug at the back for an external monitor, if plugging in a normal monitor brings up a screen, then likely the laptop monitor is defective. If you get a splash screen and bios info on trying to start it,it indicates your windows is defective or has lost it's start-up files - a windows reinstall will fix that.

Some systems may take a bit to boot at times. Windows has to do a number of functions during startup. Have you tried just leaving it run after you see the windows logo and wait several minutes? If not, give it a try. If after about 5 minutes you see nothing, get back to me.
Since the logo appears, you have video. Although the screen goes blank after this mostly means that Windows is still loading and has to perform some tasks and possible system correction issues. Let it run like I mantioned above and see what happens. Thanks

try this without battery installed. see if that does anything..

there is a hole on the back usually goldish inside take a pen push it in there hold for a couple seconds and press the power button