PC powers back on a few seconds after I "Shut down"

carwiz · 02 Oct 2011

Might be just a bad power switch or you have the Reset and Power switches reversed. Disconnet the front panel power switch and swap the reset switch (if you have one) to the Power on/off pins.

Britton30 · 02 Oct 2011

Good idea Ken. That happened to me once and I did the switcheroo. In my case I accidently broke the power switch.

@Rave, you may also try putting the power switch leads on the reset header on the motherboard as well. Using reset is not a good idea anyway.

carwiz · 02 Oct 2011

Thanks, but it's only good if it works. I'm about tapped-out as far as any other ideas. I've heard of bad power switches before and it's easy to swap the switch leads by accident during a build or repair. :) Of course, I've never done that.

debugged · 03 Oct 2011

Rave79x said:

Whilst Nesteq are not a well known brand, I think they make high quality PSUs... However, I'm running out of ideas here so I guess it could be the PSU.

This is the PSU that caused the same problem on a system I worked on a while ago. It does run very quietly, but it has its quirks. One thing is to check you have the switch (the brass dial thingy) at the back of the PSU on the correct setting (I can't remember exactly what the options are, but it might be that simple to change settings - well, you can hope!)
It hurts to change a component you spent a lot of money on, but if it fixes a major annoyance, it's worth it in the end. A better silent PSU I would recommend - 400W Seasonic X-400FL Fanless Modular - brilliant.

Atin90 · 03 Oct 2011

First, make your self a bootable floppy, if your PC has one. If not, boot to any bootable CD, DVD or USB you may have and then shut down. See if this will still give you problem
And if you still can find the cause, unplug everything from the PC, including the video, keyboard and mouse.
Do all the unplugging with the system running and use Power Button on the case to shut down. If this help, start plugging in one device at a time.
Lastly, since you were installing new SSD drives...try to boot with out this drive - unplug it, try to boot - errors are OK at this time and now shot down.
Other things that can cause this are loose cables inside PC, which sometimes can happen while you working inside the case.

Rave79x · 05 Oct 2011

Thanks again to everyone for the suggestions.

I've checked all the cables and they seem fine. I had already been using the SSD for a month when it happened and haven't been in case again, so I couldn't believe it was the reset/power leads being mixed up, or loose connections, but anyway, I checked them.

@debugged: I've contacted quietpc.com regarding the PSU as it seems far too much of a coincidence that you had the same problem with the PSU. I have an earlier model because mine does not have the brass dial on the back.

@Atin90: I'll try that soon. Thanks.

Thanks again all. Will update again.

karlsnooks · 05 Oct 2011

Rave,
Now don't you ever clear/reset the bios the way that you did. That is not exactly the best way and in case you are wondering I'm an elec. eng. with design experience.

Boot into your bios.

Choose to restore to the default settings.

Use the default settings and the default setting only.

karlsnooks · 05 Oct 2011

Rave,
When you get ready to shutdown, then:
WIN | type SHUTDOWN /S /T 10 | ENTER

WIN is the key with the wavy microsoft flag on top.

Rave79x · 05 Oct 2011

karlsnooks said:

Rave,
Now don't you ever clear/reset the bios the way that you did. That is not exactly the best way and in case you are wondering I'm an elec. eng. with design experience.

Boot into your bios.

Choose to restore to the default settings.

Use the default settings and the default setting only.

Well, OK, I'll do it your way in future. Thanks.

(I just followed the instructions on:
Guide THE BASIC GUIDE & FAQ - ABC for OCZ SSD)

I'm not doubting you in anyway, but I've read the same method in a number of places. Its the first (and hopefully last) time I've cleared the CMOS.

debugged said:

This is the PSU that caused the same problem on a system I worked on a while ago. It does run very quietly, but it has its quirks. One thing is to check you have the switch (the brass dial thingy) at the back of the PSU on the correct setting (I can't remember exactly what the options are, but it might be that simple to change settings - well, you can hope!)

and

BogdanH said:

...but there's a big chance, that your power supply unit causes this (more precise, it is +5VSB line from PSU). It doesn't necessary mean, +5VSB line it's totaly broken... can be, this line doesn't conform specification 100%, which is quite common with "no-name" units (at least, it happened to me). Btw. the problem (with +5VSB) is usually not voltage, but current!
See: http://www.formfactors.org/developer...DG_rev_1_1.pdf

The supplier has indeed confirmed its likely to be the PSU. What a shame. I don't think 4 years is a very good innings at all.

karlsnooks · 05 Oct 2011

There are many factors influencing the life of a power supply.

Mine have always outlasted the usefulness of the computer, but I do not overload them, I do not short anything, I make sure that they are kept well within their operating temp limits.

They are rather much like an automobile motor. With careful, gentle treatment and regular, frequent servicing they will outlast the usefulness of the auto.