Tech Computer keeps powering down

Subject: Tech Computer keeps powering down
From: MikeL2
Date: 18 Mar 10 - 07:52 AM

hi

I have a desktop running on Xp. It is about three years old.

Lately it just keeps powering down regardless of what I am doing.

The thing that I don't understand is that sometimes it stays up for an hour or more and other times just a few seconds or minutes.

I know that this a simple problem for the experts out there but I wouls be grateful for any advice.

Cheers

MikeL2

Subject: RE: Tech Computer keeps powering down
From: Bruce MacNeill
Date: 18 Mar 10 - 08:25 AM

If you right click on My Computer and take Manage, then Event Viewer and System, see if the system logged a failure. What comes to mind is an over temperature shut down. Frequently after 3 years enough dust accumulates in the fans, especially the fan mounted on the processor chip heat sink that it stops the air flow, the system senses heat and shuts down to protect itself. There should be some kind of log entry to say why it shut down unless it's a power problem, loose wire or something like that. Assuming it was a logical shut down for self protection, there should be a log entry.

Subject: RE: Tech Computer keeps powering down
From: Jack Campin
Date: 18 Mar 10 - 08:35 AM

Flat PRAM battery on the motherboard?

Subject: RE: Tech Computer keeps powering down
From: Nick
Date: 18 Mar 10 - 09:20 AM

Good time to back up any information you have just in case.

Iffy fan seems or overheating sounds very plausible

Subject: RE: Tech Computer keeps powering down
From: Edthefolkie
Date: 18 Mar 10 - 09:24 AM

Like Bruce, I'd try a good clean first. I had the same problem last summer (not THAT hot in the UK!). I downloaded a freeware product called CoreTemp - see http://www.alcpu.com/CoreTemp/ and was fairly astounded to find that both cores of the processor were running at well over 85 degrees centigrade.

I had a look at the fan on the side of the case and this had quite a lot of cat hairs in the mesh (Birmans and computers don't mix). There was also a lot of dust round the processor board and fan. Easy to clean with the crevice tool on the vacuum cleaner, but make sure the box is powered off and disconnected first, also don't knock any connectors!

I had another look at CoreTemp afterwards and the both cores were running closer to 32 centigrade.

Subject: RE: Tech Computer keeps powering down
From: MikeL2
Date: 18 Mar 10 - 03:45 PM

Hi guys

Many thanks to all for the information.

I cleaned the filter and the fans and generally around inside.

I have been up now for over a couple of hours so it could be that you have identified the problem for me.

Fingers crossed.

Thanks again

Cheers

MikeL2

Subject: RE: Tech Computer keeps powering down
From: gnu
Date: 18 Mar 10 - 04:25 PM

Me too. Good stuff. Thanks.

Subject: RE: Tech Computer keeps powering down
From: Stilly River Sage
Date: 18 Mar 10 - 04:31 PM

Meanwhile, you might want to price power supplies. That is often the culprit in this kind of problem and this might be a sign that it's getting ready to fail. They are relatively cheap and are easy to replace. Be sure to get one that fits your computer, but it doesn't necessarily need to come from the manufacturer (those are typically over-priced).

SRS

Subject: RE: Tech Computer keeps powering down
From: Bruce MacNeill
Date: 18 Mar 10 - 06:10 PM

SRS has a point but that's why I wanted to know if there was a log entry. If the system powered down for self-preservation, there will be a log entry to that effect. If the power supply shut down on it's own, there may be a log entry about starting up from an unknown condition or just the normal start up log entries. Meanwhile, if it stays up, it was just dirty and you'll have to clean it periodically. A toothbrush is goof for taking out the stuck on dust but don't brush your teeth with it afterward.

Subject: RE: Tech Computer keeps powering down
From: JohnInKansas
Date: 18 Mar 10 - 11:10 PM

Point of reference:

astounded to find that both cores of the processor were running at well over 85 degrees centigrade.

85C was a commonly used "junction temp" for "doped silicon" transistors in "high reliability" applications about three decades ago. Much higher and the dopants might migrate and reliability went down. Commercial grade devices were running up to 105C, and sometimes 135C even then in some cases.

Since the development of "FET" xistors and higher density designs (smaller switches) 135C was pretty normal for a "design limit" junction temp in "industrial grade" stuff; and higher design limits probably were fairly common in non-critical devices.

These are "junction temperatures," in the inside of the individual devices; but the "bulk temp" of a processor may be pretty close when things get packed close together.

Reliability is better if the temps are kept lower; and since "user machines" seldom have really tight temperature regulation, it's risky to work too close to the limits for normal operation.

I haven't seen anything on recent designs, and the temperature indicated by the program used likely is just an average for the whole processor; but they do run a lot hotter than seems reasonable.

A look at some of the sites popular with people into "overclocking" might give more up to date limits; but some of those guys burn up processors on a regular basis.

John

Subject: RE: Tech Computer keeps powering down
From: Dave the Gnome
Date: 19 Mar 10 - 07:21 AM

Mike - If you decide you do need a new PSU check your PM's

Dave

Subject: RE: Tech Computer keeps powering down
From: MikeL2
Date: 19 Mar 10 - 10:41 AM

Subject: RE: Tech Computer keeps powering down
From: Bruce MacNeill - PM
Date: 18 Mar 10 - 08:25 AM

Hi Bruce I have sorted out my computer with the help of a pal.

But I have done what you said to try to find what it said on the log.

When I right click on My Computer I can't see any access to MANAGE.

I have also tried it on my laptop ( Vista) and can't find it there either.

Cheers

MikeL2

Subject: RE: Tech Computer keeps powering down
From: MikeL2
Date: 19 Mar 10 - 10:48 AM

hi dave

I have PM'd you .

Many thanks for the offer to help.

Cheers

MikeL2

Subject: RE: Tech Computer keeps powering down
From: Joe Offer
Date: 19 Mar 10 - 11:00 AM

I had this happen in XP after I installed a program. I had to start XP in Safe Mode and then uninstall the offending program.
So, you may want to think back on what changes you made to the computer at the time the problem first occurred.
-Joe-

Subject: RE: Tech Computer keeps powering down
From: JohnInKansas
Date: 19 Mar 10 - 11:54 AM

MikeL2 -

The management tools, since WinXP, have been different between the various versions. Many of the useful tools are NOT AVAILABLE in "Home Basic" (I think that was the name?) and you need the Home Premium(?) or Professional(?) or Business (?) or MultiMedia versions to have all of them. (At least this is the way I remember XP.)

I don't know whether the "click" referenced is one that was omitted from the starter version though.

Microsoft has done such a poor job of telling you what the differences are between versions, that it doesn't really do a lot of good to tell someone who offers advice what version you have, since the only way for them to know whether you have all the buttons they have is if they are running exactly the same version you have.

In the cheapest version, many tools simply aren't there, and can't be added without upgrading to a higher priced version. As you move up in price, some tools aren't installed by default, but can be added if you can figure out how to put them in. The top line (top priced) versions generally have almost everything turned on at installation.

If you can figure out what to ask, articles in Windows HELP sometimes include a link to open things that aren't where they should be (or where sane/rational people would expect them to be), and sometimes consulting the link in Help is the best way to do much of anything useful in the more basic versions.

An unlikely, but easy(?) to check, possibility when unexpected power-down is happening, is that the timeout settings, or the "what to do" settings, in Power Management have gotten changed. While I haven't seen anything like what you've described, I have seen settings change mysteriously, in several OS setups since the "green machine" notion wormed in; and almost all machines since the late Win98SE geological epoch have included automatic time-outs to conserve power.

John

Subject: RE: Tech Computer keeps powering down
From: Mick Pearce (MCP)
Date: 19 Mar 10 - 12:33 PM

If Manage is not in the context menu on My Computer, you could look in Control Panel/Administrative Tools. (On my XP/Pro the Event Viewer is in both). (But as JiK says, it may be only available in Xp/Pro).

Mick

Subject: RE: Tech Computer keeps powering down
From: Bernard
Date: 19 Mar 10 - 03:05 PM

It's definitely there in both XP Pro AND Home - if it isn't, it's usually because malware has removed the registry entry... and maybe other things are missing, too.

Quite often you will also find that Safe Mode prompts for a password that you know isn't set. That's because the malware doesn't want you to find and remove it.

You could try creating a shortcut pointing to:

%SystemRoot%\system32\compmgmt.msc /s

Subject: RE: Tech Computer keeps powering down
From: MikeL2
Date: 19 Mar 10 - 03:39 PM

Hi Bruce

Thanks to MCP JohninKansas et al I have found the event viewer in Control Panel/Admin tools.

I checked and there was no event logged that looked like it was taken down because of heat safety.

Many thanks to all who helped and are still helping. I am finding out lots that I just didn't know.

You lot are just great.

cheers

Mikel2

Subject: RE: Tech Computer keeps powering down
From: Stilly River Sage
Date: 20 Mar 10 - 12:52 AM

Alas, one of the times when we learn the MOST about our computers is when they cease to operate, or operate correctly.

Subject: RE: Tech Computer keeps powering down
From: MikeL2
Date: 20 Mar 10 - 05:45 AM

Hi

<"Alas, one of the times when we learn the MOST about our computers is when they cease to operate, or operate correctly.">

Now I know why you call yourself Sage......lol

Cheers

MikeL2

Subject: RE: Tech Computer keeps powering down
From: JohnInKansas
Date: 20 Mar 10 - 11:45 PM

And all this time I thought it was fer smokin' funny stuff.

John

Subject: RE: Tech Computer keeps powering down
From: Bruce MacNeill
Date: 21 Mar 10 - 01:38 PM

I've been out of town for a few days. Is the machine still up? Whether anything got logged depends upon what machine it is, which we never discussed. Anyway, if it's still up it was probably just over heated from dust. If not, and there's no log entry, the power supply is the primary suspect but generally when they go bad they stay bad. There's a little fuse inside the power supply box, not designed to be easily replaced, which generally blows before all the smoke comes out.