First check: can you get an image on an external screen?  Any beep codes or LED flashes?

theres isnt any beep only light in the screen and nothing else

Basic troubleshooting:

Disconnect the AC adpter and remove or disconnect the battery. Remove and reinstall the memory module(s) from the system.  Disconnect all USB devices from the system.

Verify that the LED on the AC adapter (or DC jack) is ON before you plug in the notebook end.

Try powering up on AC only.  If it will but won't with the battery installed, the battery is faulty.

If the system still won't complete POST, the mainboard is bad.

that dont work,,, but i change multicore in the bios and set it to 1 and it work but anytime i put it to 2 it return to the black screen

What model CPU is installed?

intel core i5 520m with nvidia 3100m

any help yet

This is either a bad mainboard or a bad CPU - the odds are much more likely it's the board than the CPU.  Replace that first.

you could try updating the graphics drivers. then open start and search for dxdiag and open it, then click on display and check if the Graphics is displayed.

you can update the drivers by opening start, right click on my computer/this pc, click on manage, then click on device manager and under display right click and update the driver.

hopefully this will help

my graphic driver is already up to date,, ill say that my main board is damage.