I've bought a new raspberry pi with a power adopter (5V, 3000 mA). I've written the rabian(2018-06-27-raspbian-stretch.img) image in sd card(8 gb) using win32 Disk Imager. the red light is active, while the green light has an irregular blink. when i connect it to the screen i get "there is no signal". Could you help me please?
It sounds like your display is a bit quirky, at least to the Pi.
Look in the first partition on the SD card (it will be the only one you can see with MS Windows). Find the file named
config.txt. Open it and add the line:
Now try and reboot. For more information see https://github.com/raspberrypi/documentation/blob/master/configuration/config-txt/video.md