5ish seconds after turn on, 3 beeps and blinking red light

Had my ps3 since Christmas of 09 (fat model I guess? 2nd gen? Was newest model when I got it I think) and used very regularly since, no issues over the years. The other week, after bringing controllers (original) back from using at my grandpa’s with his ps3, i re-synced them to my system and played some ncaa football 13 road to glory. A few days later, I went to turn it on again using controller, and after about 5-8 seconds of seemingly normal start up, it turned off with I believe three beeps. The controller flashed all four lights red like it would if it wasn’t synced, and my ps3 light blinked red until I pressed it again after a few secs, then it went back to solid red. I tried it again a couple times by pressing the power button on the system, but with same result. Gave it a day, did research, so in general I have an idea of potential issues. Vacuumed out all vents and surfaces, seemingly got plenty/all of lint and dust out. Gave it a couple more tries, still same problem. Hoping that maybe detailing the whole issue might give someone on here a better idea, as I’m not console tech-savy and would hope to avoid any repairs that are too complex. If taking it apart and thoroughly cleaning fan, or replacing thermal paste, etc is the only option, I’ll do anything to try and fix my beloved. Doubt it has any correlation whatsoever, but a couple days before this issue, I asked my gf to log out my PSN on her PS5, so I could get online on my ps3 again. Again probably zero chance of any correlation there, just wanted to provide all possible context in hopes someone might know the problem fix. Over the last 5+ years, it’s been in transit a ton coming with me to and from college, but never dropped or handled roughly to my knowledge 🙏🏻🙏🏻🙏🏻