Computer Tries to Boot but keeps shutting down.

Hello! I had acquired as of recently a new 3440x1440 monitor from massdrop which I had been troubleshooting for the past 2 days to see why it wasn't connecting to my laptop which is an ASUS G751JY-DH71. I have had the laptop for about...I think 3-ish years at this point. It has a 980m graphics card 250GB SSD, and 1 TB hard drive.

Well I got the monitor to work after I changed the hdmi cable, it was running just fine while I was tweaking with some settings and then suddenly turned off. I unplugged everything and tried turning the laptop back on and sometimes it get past automatic repair and shut off or shut off as soon as I turn it on.

Now this is the second time this has happened in a span of 3 months, the first time it did it we took it up to a local repair place. Which I figured it was just the laptop finally beginning to overheat, I was correct and we got the laptop apparently professionally cleaned and working again. SSD and Harddrive were both in good health. Now this is the second time, I followed a tear down of a similar laptop on the site, took it completely apart and at least tried to remove some of the dust with a can of compressed air. Which it looked quite dirty despite apparently it was being cleaned. I'm pretty sure it's not my SSD or Harddrive since we got those checked when it initially happened as well, not a single problem. Is there any tips possibly someone has on cleaning? Does it sound like the overheating issue again? Or like a component failure? When I cleaned it with a can of compressed air it nearly restarted all the way and even made it past system repair before shutting off, now its struggling to get past that.