When trouble shooting sometimes chips, caps or resistors can get much hotter than surrounds parts. It can let you know to inspect that part for replacement.

Sure don’t grab leads with your fingers but sometimes you can tell something like a voltage regulator is malfunctioning because it just gets really hot.

I mean you can just use an IR camera but most people don’t have one.

Not usually… I mean please do read up/watch some youtube videos on electronic repair safety, but for the most part the power supply of a ps1 lives in the unpleasant shock realm of zapping power.

Talk like this scares people away from doing their own repairs.

Looking at cost of ownership. Spending maybe $100-200 every 20 years is really good. Repair is an option

I’m no expert either but a first step would be to take the case off and listen for which part the whine is coming from. That may clue you in.

You can also touch parts and see if any are extra warm/hot soon after start up.

That can help direct your trouble shooting.

Don’t buy parts until you have a clue as to what might be happening. It’ll save you money.