Laptop DELL after startup the screen goes black

Hello,

Hi guys I just formatted my laptop then suddenly after startup the screen goes black. I don't know how to fix this I also didn't complete the windows 7 installation when I tried to format it because after startup the screen goes black like I waited for how many hours yet nothing happens, I also tried the method remove the battery and press the shut/on button for 20 sec. to 2mins yet nothing change