Power Issues

[Deadmeat]

Over my years of visiting this forum I've seen a lot of posts concerning this issue. System that wouldn't start, would reboot on their own, or would shut down. So, I thought I'd share what happened to me.

Yesterday I finished up a case mod on my second rig that involved repositioning a cold cathode tube, tidying up the wiring and installing a full plexiglas side panel. Powered it up and all's well. Ran all day and into the night without a hitch doing its folding thing and I use it for chat. I shut it down sometime after midnight and went to bed. This morning I hit the power switch and got nothing, nada, zip, zilch, zero. Pushed the switch repeatedly. Still nothing. The power LED on the mobo is on and my other rig which shares the same power source is running, so figure it's not house power. Check anyway. Yup, 118 volts at the power cord. Plug it back in. Still nothing. Time to pull the side panel. At this point I'm starting to question my German heritage which allowed me to overzealously engineer no less that sixteen screws in this thing when I reach over the top of the case to steady it and it boots. WTH! I didn't touch the power switch. I reach over again and it reboots. Once more and it shuts down. I find that if I barely touch/move the case something happens. Static? Unwisely it's on the desk and I'm in stocking feet on a carpet. So, off to the workbench where it's placed on a static mat which is connected to house ground, the case and a wrist strap to me. I recommend anyone who touches the insides of a computer use one. Some time ago I learned the hard way about static electricity when I burned up a mobo and cpu. I got mine at Radio Shack for $25.

I'm an Automotive Technician by trade so I know about DC power, but I don't know what happens inside a mobo. I do know, however, that the power switch closes a circuit in the mobo which allows it to turn on the PSU. So, I'm thinking that circuit is already closed as I haven't touched the power switch since initially plugging it in, so something else is loose. I take a screwdriver, just touch the ATX connector harness and it reboots. Successive tries yield the same results. I pull the ATX harness and clean both connectors with a cleaner spray, canned air and a blower to get them nice and dry. Plug them together, hit the switch and Viola! it boots. Now the test. I shake that case like a hungry ape in a cage and nothing happens. It's fixed.

I'm sure, by now, some of you feel I've been rambling, but I felt I had to tell the whole story. The point I'm trying to make here is GET DOWN TO BASICS. Before you start swapping out components where you might unknowingly "FIX" something without getting to the source of the problem, check and clean connections. Computers run on low voltages with minimal amperage and it doesn't take much dust or corrosion to disrupt a circuit.

I hope this will be of some help.

[Mobius]

Yeah Jax - I've spent so much time debugging a PSU cable not properly seated/making contact on the motherboard - it's positively scary! Now, when I encounter power issues, the very first thing I do is unplug the PSU from the mobo, give the thing a good blow, and seat it firmly and wiggle it a bit. That usually fixes it!