Pc wont start at all

Hi all

My pc wont start at all. I have had some problems with it the last 2 times i started it. I will be watching a series or something and it will just completely freeze. I decided to reinstall windows after doing a system recovery and after that i cannot even awitch the pc on. It will go on but absolutely nothing on screen and it will keep restarting with nothing at all. I changed the ram to a different slot, unplugged the extra hard drive but it still wont start. Any help will be appreciated. Thanks!