When i power on my pc moniter not started hard disk light not blinking..

Are you powering on your computer and your monitor...

If your computer appears to boot, but nothing on your monitor...
Here's some tricks I would try. Something here, might help...
1. Verify the monitor's power cord is plugged firmly into the wall outlet and the back of the monitor.
2. Verify the monitor cable is firmly connected to the computer and the monitor.
3. Verify that you have turned the monitor power switch on.
4. If the power light on the monitor is not on, test the wall outlet (plug in a light or something you know works).
5. If the power light on the monitor is not on, try a different power cord.
6. If the power light is on and yellow or orange or flashing, but nothing displays, or the display is incorrect, borrow a monitor from a friend. If that works, your monitor probably needs replaced.
7. Also, you could try your monitor on a friend's computer. If it doesn't work, your monitor probably needs replaced. If it works properly on your friends computer, the problem may be with your computers video output port, motherboard video chip (or video card, if you have one), or drivers.
Good luck.

If your computer won't boot...
The hard drive, motherboard, or some other critical component may be failing, or just the OS or hard drive corrupted. If you have files that you do not want to lose, you could try this... Pull the hard drive out, and use a "USB Hard Drive Adapter" (available fairly cheap online) to connect the hard drive to a friend's computer, and save all the personal files (documents, pictures, etc.) you can to a folder on the friend's computer or an external hard drive. That way, at least you may not lose your files.
Then, you could try to do a Factory Restore or Reload on the computer, and if that works, copy your personal files back to your newly restored computer. Good luck.