Old Ps4 will glitch out and then shutdown?

As of a couple months ago, my ps4 (not coming from ps4 itself but the tv audio) just randomly started screeching combined with the screen glitching out and flashing a bunch of random bits before it completely shut off. after a long period of testing, the ps4 will also do this same thing if i press down on it in the top right quadrant, or sometimes if i play a game that is intensive. (i.e. bo4 will kill it but hollow knight is fine). although there has been periods of time where it's worked without problems (aside from it shutting off and glitching out if hit or bumped around that area), but it will eventually start crashing again. I believe it might be the power supply but i haven't seen this happen to anybody else on any forums so im confused. also it is very dusty on the inside and would have the fans spinning constantly despite where i had it (out in the open or in a cabinet)