I had a problem in the HD previosly but I was busy too much so I left it after 4 month I brought a new hard disk but my PC want work at all!

When I plug in the power my pc's bottun start blinkin without any response to other action also there is no any display on the screen I don't know what is the prob

Kindly help me...

Did you replace the old hard drive?

Is there any operating system installed on the new hard drive?

I replaced the old one
There isn't any OS currently actually there is no display n the start bottun of cpu in not responding just blinking

Check to make sure the drive is set to master via the jumpers if the drive has jumpers, if it does and the drive is set to master, change it to CB - cable select and try to boot.
Make sure the drive is attached to the end of the ribbon cable in the PC and not the middle connector on the cable
Make sure the red side of the cable is facing the power (where the power is plugged into the drive)