subject: My PC power supply randomly shuts down? [print this page] My PC power supply randomly shuts down? My PC power supply randomly shuts down?
on my SMPS Tech Web site I present a general method of problem solving. To solve any problem, you first have to know there is a problem, that it is relevant, that it is solvable (preferably by you), and finally what the solutions is.
Your reader certainly knows he has a problem and that it is relevant to him, so the next step is the ask if it is solvable, preferably by him. The approach he took, a good one, was asking help from a guru.
Is the problem solvable by a remote guru? The answer is no, with an explanation.
The bottom line is that there is not enough information in the email, or could there ever be, to solve the problem. Having said that, your reader has shown remarkable troubleshooting skills. He has virtually eliminated the power supply as the problem and isolated the problem to the load, probably the mother board and its sensors. (A 90% probability SWAG, which means there is still a 10% chance it is the power supply or one of the motherboard plug in boards or a chassis mount component such as the fan.) The power supply is probably doing what it was designed to do, protect itself from a malfunctioning load.
And what do we know about motherboards? That they often have "intermediates". Which are one of the toughest problems to isolate. A frequent cause is a trace opens ups or shorts if the board is flexed or changes temperature. And these are very tough to find, especially on a multilayer board where all traces are not visible.
The only advice I can offer your reader is to do a very careful visual inspection of the the mother-board or any other circuit board looking for cracked traces, discolorization and any component that looks discolored or in other than pristine condition, as I explain in my article on Troubleshooting Power Supplies. This is a remarkably powerful technique.
What I have described is a systematic and logic way of finding the problem. There are two others, finding someone who has had the same or similar problem and hope they have a canned answer. Your reader had done this and may have presented his problem on other venues. This is always worth a try and sometimes works -- but don't hold your breath waiting for an answer. The other is trial and error stabs in the dark. Again, don't hold your breath.
The bottom line is, this problem is unsolvable by remote gurus like us. Your reader has the mother board, eyes, and hopefully a multimeter to check for opens and shorts. If he can't solve it this way he may have to replace the mother board and other components and see if new components solve the problem.
