getting black screen after installing of windows8 os...iam using dell inspiron, nd same os is working fine in other laptops

Try hooking it up on a monitor or a TV with an HDMI or VGA (worked for me on HDMI). You won't have a black screen on the TV or monitor so you can install the graphics drivers on the laptop and mess around with the settings to get the laptop's monitor working, or (if you can) just install Windows 8.1 it should work.