power butten don't work

Hi @yaredtaye!

Do you have a multimeter? If so, remove the power button board from the computer and follow this guide to check the button for continuity. If the meter beeps while you push the button, it is functional. You may have to experiment to find out which line is which. If it isn't faulty, you may have a problem with the cable connecting the board to the motherboard, or the motherboard itself. If indeed it is faulty, you should be able to find a replacement board on eBay or just solder a new button in.

Good luck!