PSUs can really cause weird issues when going bad

[Heywould3]

I thought I would share some info on a computer issue I have had. First I had an old computer that worked fine but packed it away when I built a new one, I took it out of storage to give to one of my kids and it was acting strange, for example it wouldnt boot with the power switch unless I held the switch for a few seconds and released then pressed again, (that worked most of the time but not all) before you say BIOS, trust me I looked into that in great detail. I spent weeks off and on messing with all the components, I would have looked at the PS right off it had been flaky once started, once started it ran fine... after many trys i just gave up, gave it to my kid and just told her how to power it up. months went by like this and i got her a new one, I then gave it to my dad (its an AMD X2 with 4gigs) still good enough for him, he had the same issues..

Flash forward to a week ago, I started having trouble with my current build, first it would not wake from sleep. i messed with all sorts of things including bios thinking something must have changed, I was never able to get it fixed so I just turned it off instead of sleep, moving forward to a few days ago it started not turning on. I then got the idea to hold the power for a few seconds and try again.... what do you know, it started..... hmmmmmm.. strange.. I did a little messing with it then decided to get a new PS in a last ditch effort, staples had the Antec 550pro on sale for 55 (the black modular version) i poped it in and WOW, its so much better than it was before it started acting up.. it must have been sending low voltage for a while causing faults because it starts instantly now( SSD drive) and everything just pops right up..

The PSU was an antec 500 that was in it already.

So, I guess the moral is that when all else looks ok, try a new PSU.... Now I can fix my old computer too and give a little more life to that one.

[jman98]

Thanks for the info. I work in IT and I've seen some absolutely bizarre PSU related problems over the years. My rule is that when you have a bizarre problem on a PC that defies rational explanation, consider the possibility that it's really a PSU issue that can only be fixed by replacing it.

[hello_hello]

Interesting.....

I have an old(ish) Antec PSU floating around here somewhere which was doing something similar. A 500w model, I think. I'd used it to run a particular PC for quite a while and it worked flawlessly. I can't remember the details of which PC it came out of and which one it went into at the time, but anyway, when in the original PC it never gave me a problem while the second it went into the new PC I had startup issues. I don't think I ever tried the "hold the go button for a few seconds" startup method to see if it'd work, and I never put my PCs into sleep mode so don't know if it would have still behaved the same way, but basically when I pressed the go button I'd get a little flash from the front panel LEDs, then everything would go dead again. By pressing the go button enough times I could eventually get the PC to start up and it'd work normally.

Of course I got sick of all that pretty quickly and replaced it with a new PSU and everything worked fine, but around the same time I read some info on power supplies and startup issues, the upshot of which seemed to be: switching power supplies require a minimum load to start up, and if they don't see that load they'll simply switch themselves off again. This is one of the articles I read at the time and it specifically mentions Antec Neo power supplies as being one of the most well known culprits for causing start up problems due to higher minimum load requirements. http://www.playtool.com/pages/psuunderload/mincurrent.html

In my case once the PC did begin to start normally it started up and continued to work flawlessly which also made me think the minimum load problem could be the cause. I guess for it to apply to your issue the minimum load requirement of a PSU might need to change a little as it ages otherwise you'd think once it's working with a particular hardware configuration it'd just keep working (unless you did move hardware around a little?), but I thought I'd post the info in case you might want to try loading it up some more to test it out for yourself. Obviously, I haven't found the motivation yet.....