Question Computer won't startup - not even powering up


Sep 29, 2015
My computer is not really old (3 years old), worked great, and lately had issues that when I clicked the power up button, it didn't start.
After a while when turning on my AC in my room, it started to work (not sure if it's related..) but it worked like that for a while (and the clock of the PC was incorrect when turning on randomly)

Until 2 weeks ago. I'm trying to power it up - with and without the AC on - and it's not powering up. I'm afraid it was an issue in the Power supply, but I'm not sure. I never had such an issue that the computer doesn't startup, even no lights.

So.. I'm posting here to get some advice. My options are:
  • Take it to a technician and wait 2 weeks to fix it
  • Try and replace the power supply myself, and hope this is really the source of the issue.
Any idea why such an issue could happen? Any suggestions on what to check?
* Already tried to connect it to another power source in another room - didn't work.

Thanks in advance! Any advice can help me a lot..