PEBKAC

November 19, 2006 8:41 PM

Just a couple weeks ago, my computer was so cooperative. Now I'm getting freeze-ups at the strangest times. I'm the definition of an End User, but with AskMe's help, I might just get XP tamed!

About a week ago, my computer started freezing for reasons I can't explain. At first, this only took place when we shut off the screen saver, then forgot to reactivate it. It would go into a sleep mode that turned out to be a coma. It took a press of the reset button to regain control.

We reengaged the screen savers, but then she started locking up during simple operations. Web browsing, moving files, simple stuff that shouldn't even be a trickle to my gig of RAM.

I've eyed the process list, but there doesn't seem to be anything there that shouldn't be. There's about half a dozen SVC host shells running, but these were there before the problems began. I realize this is a bit vague, and that Windows XP can freeze up for a lot of reasons - but I'm hoping that, if nothing else, the suggestions of MeFites more knowledgeable than I can at least get my computer and I on the road to recovery.

posted by EatTheWeak to computers & internet (24 comments total)

Did you happen to install any new drivers in the last week? The newest ATI drivers were causing some similar-ish problems on my machine just recently.
posted by Dipsomaniac at 8:57 PM on November 19, 2006

1. Search the archives
2. Tell us what you've done so far

Then:

What did you install before this happened?

Google for 'Crap Cleaner (CCleaner)'
Get antispyware (2 or three kinds like adaware spybot and ewido, try not to get the kind that actually installs spyware)

Run a virus scan.

Turn off power management (there's a bug in this that causes some of the symptoms you're describing)

How much of your ram is being used up? (check under performance tab of taskmanager) What's using it?

SVCHost can, in fact be a hiding place for some crap.
posted by IronLizard at 9:01 PM on November 19, 2006

In addition to the spyware cleaner (I recommend spybot), make sure that your anti-virus is up to date. Get AVG free if you need a new one.

Also be sure that your hard drive isn't completely full - clean it out and do a defrag.

Is it a freeze, or does the computer reboot itself? The latter can be indicative of overheating.

Go through the last few weeks in your head - what have you installed?
posted by chrisamiller at 9:06 PM on November 19, 2006

Note: AVG Stops being free in january.
posted by IronLizard at 9:14 PM on November 19, 2006

You won't believe this - while trying to update this thread, she froze up again! While rebooting, it went into Scandisk, saying one of my disks needed to be checked for consistancy. Then a whole host of orphan files were apparently purged. Or something.

Okay, let's see - I use Hitman Pro for Spyware killing and AVG for virus protection.

Dipsomniac - No recent driver updates that I'm aware of, though I did let Windows update itself. I stopped it the first time it tried, as Internet Explorer 7 was among the things to install. I took that off the list and gave it another go. It seemed to take, at least.

IronLizard - please forgive my ignorance, but how does on search the archives. In the past couple weeks, we've installed TVU player and uninstalled a Nero 7 demo.

Any tips on spotting crap hiding in the SVC host?

chrisamiller - Loads of harddrive space left. This is a definate freeze - I gotta force it to reboot afterwards. Scandisk and Defrag took place about a week ago, when my troubles began (or I began to detect them).

Thank you so much, folks. I'd like to send you all lovely gift baskets.
posted by EatTheWeak at 9:21 PM on November 19, 2006

IL - next to no ram is getting used at all. the little green line is quite flat.
posted by EatTheWeak at 9:23 PM on November 19, 2006

Any tips on spotting crap hiding in the SVC host?

Sysinternals Process Explorer It's a tedious process. The last time I went paranoid apeshit, thinking I had a rootkit and combed through everything with procexplorer and Hijackthis and IceSword and Rootkitrevealer, I was unhappily vindicated. Point me at a PC that's regularly on the internet and the user(s) download regularly and I'll show you at least one peice of nuisance-ware.

Search the archives in the little search box on the upper right.

There may also be bad sectors on your HD from the sound of things, especially if your paging file is located on a couple of them. Run scandisk again in thorough mode (or better, find a better disk checker utility and no, I don't know which one)
posted by IronLizard at 9:35 PM on November 19, 2006

IronLizard - AVG Free 7.1 is being discontinued in January, but the new version (7.5) will still be free.
posted by djb at 9:44 PM on November 19, 2006

Also, this may help.
posted by IronLizard at 9:46 PM on November 19, 2006

but the new version (7.5) will still be free.

No kidding, that's great. Maybe I should have checked the website instead of relying on the programs new pop-up notifier. I dreaded having to source a new anti-virus.
posted by IronLizard at 9:48 PM on November 19, 2006

Honestly...I would cut to the chase, back up all your data, and reinstall windows. That is, if it has been a while since you have done this. Reinstalling will not only make your system run better, but it will solve this problem.

And hey...if it doesn't, then it sounds like one of your hard drives is going bad. Call it extreme troubleshooting.

:)
posted by ampersand2001 at 9:50 PM on November 19, 2006

Well, sure. But how much fun is taking the easy way out and what would he need our advice for then? If I had a penny for every hour I spent blissfully poking around the internals of my operating system, why I'd have..... well a few bucks anyway. Re-installing is for wimps. We're trying to edjumucate him.
posted by IronLizard at 9:55 PM on November 19, 2006

It would go into a sleep mode that turned out to be a coma. It took a press of the reset button to regain control.

Just let me re-iterate one thing, turn off power management.
posted by IronLizard at 10:05 PM on November 19, 2006

Power Management = bad

Running AVG right now. No hits yet. I shut down power management once it finishes.

Edjumucation is absolutely the goal. So very tired of pawing through the dark with this thing.

Thank you so much.
posted by EatTheWeak at 10:11 PM on November 19, 2006

The overheating idea is good. Computers do all sort of weird broken things when they are on the edge of overheating, then they crash. Open the case and check to see that the fans are spinning correctly.

I am the big fan of reinstalling myself. I use Linux in parts because I find that such instabilities are impossible to debug in Windows. Windows is very much a black box.

It is worth buying and extra hard drive and an enclosure. It will serve you for both your regular backups and for your occasional reinstallation.

Once you have a clean install of Windows, you should make a backup of it with partimage so it that the next reinstall proceeds faster.
posted by gmarceau at 11:19 PM on November 19, 2006

[insert macro name="Get a Mac and save months of your life already"]
posted by rokusan at 2:58 AM on November 20, 2006

I am thinking power management really might be it, or else a hardware issue. Sounds like your computer is running perfectly fine and this is not a virus/spyware issue at all. It is either a driver or hardware level problem if you are getting lockups like you describe.

I would run memtest86 and prime95 to test your memory and then (if ram is not at fault) start thinking about backing up your data before your hard drive dies.
posted by sophist at 2:59 AM on November 20, 2006

I second overheating. This happened to me a few years ago, and it turned out that so much dust had gotten in my case that every fan had seized.

If you open the case (which you should probably do before reinstalling Windows), you may have - depending on your system - at least one fan bolted to the case, one on the CPU, and one on the motherboard. Check those and make sure they're all blowing air.

If any of them are stopped, the hardware's probably fried.
posted by backseatpilot at 4:21 AM on November 20, 2006

Not to hijack this thread but when I go to the AVG page and read the info for 7.5, nowhere does it say "free version". It says, "buy", "info", "trial." djc, are you saying that the trial version is the free version? Because I have several machines I will need to source a new free antivirus product for in January, otherwise...
posted by Lynsey at 10:00 AM on November 20, 2006

Lynsey:

They are using the same strategy ZoneAlarm and others have been using. They continue to offer the free version, but they hide it well on their website so that unless you are really determined, you pretty much give up and pay the few dollars they charge for their paid version.

If you go to this list of their products and scroll down all the way to the bottom of the page, you'll see a link for the free version, which will take you to this page about the free version
posted by tuxster at 12:41 PM on November 20, 2006

Upon reboot, does the system log show any fault information? For example, does XP pop up a message that says "the system has recovered from a serious error", or are there any entries in event viewer? This could be a clue as to whether the issue is related to software (example: drivers) as has previously been posited, or if the problem is in fact related to hardware (in which case it could be that nothing gets written to the event log).

Shutting off power management is a good idea for troubleshooting purposes.

The advice about overheating is very good advice. You might wish to open the case carefully, and use compressed air to blast the dust from the CPU fan and out the back of the power supply (and be sure to blast it AWAY from the motherboard -- you don't want dust getting into the expansion slots or even touching the board, b/c dust can carry a static charge).

Speaking of static -- whenever you open the case, make sure you're grounded so as not to make matters worse via electrostatic discharge. The best way is by standing on an anti-static mat, and using a wrist strap. The poor man's way (in a pinch) is to limit your movements (don't shuffle your feet across the carpet -- in fact better if you can bring the PC to the kitchen table and stand on linoleum or tile etc), leave the PC plugged in but powered off (so at least the PSU is grounded via the outlet) and make sure you're touching bare, unpainted metal on the case with one hand while doing work with the other hand (so your electrical potential is as close to that of the box as possible).

One other very common (and often overlooked) factor in spontaneous freezes/reboots is a faulty power supply. In my experience a good deal of flaky behavior in PCs begins with an underperforming/overloaded power supply. (This sort of thing often arises when a new CD-R drive is added, for example.) If you have one of those setups where you're daisy chaining surge protectors, or have too much on one circuit, that can be an aggravating factor. But the voltage from the wall (which can drop temporarily when something on the same circuit kicks on, for example) is often inconsistent enough to cause a drop in DC voltage and cause a (temporary) failure of components (CPU, RAM, HDs, etc).

This undervoltage often causes additional problems as system data on the drive can be corrupted by underpowered components -- dirty data gets written, machine hard reboots before disk caches can be flushed, or freezes in the middle of a disk write, etc. Over time, a PC with a flaky power supply begins to resemble something affected by viruses as your hardware problems beget software problems.

In a case like that, the typical diagnostic action would be to backprobe the power supply with an auto-ranging digital multimeter. If the power supply tests show leaky grounds or volatges outside of accepted tolerances (which is +/- 5% for the ATX spec) then you replace it. This is probably beyond the scope of home repair by non-technical folks (and unsurprisingly, beyond the expertise of the all-too-prevalent semi-pro "backyard mechanics" at the local computer shop.) But if anyone's interested in learning the procedure, I'll post it.

Another possiblilty is faulty RAM. I'd start with the other things first, because testing RAM for errors can take many hours and is less likely than bad drivers, overheating or a faulty PSU. But if you get down to that step without any joy, we can cover testing memory.
posted by edverb at 6:48 PM on November 20, 2006

edverb - I'd love to know the backprobing procedure.
posted by djb at 8:32 PM on November 21, 2006

djb...sorry for the delay, I didn't see your reply until now.

OK...backprobing an ATX power supply. All the usual anti-static procedures apply. Ideally, the PC will be plugged in and turned on, with all components remaining as they are in a production system. (You could perform this procedure with the drives out, PCI cards removed etc, but ideally you want to test the power supply with components drawing a load as they normally would, so leave them in.)

So what you have is a PC plugged in, turned on, with all the components in place, with the side of the case off.

It's important that you use an digital autoranging multimeter for this, not an analog multimeter (analog multimeters or non-auto-ranging ones can give a slight charge and can zap components on the board.) Here's an example of a digital auto-ranging multimeter. You would follow the instructions in the manual for testing voltage, and set the dial accordingly.

The multimeter uses two probes, one black and one red, plugged into their respective ports on the meter.

The PSU has several types of connectors on the DC side (inside the PC) -- what you're looking for is the big harness (20 pins) which connects the PSU to the planar.

="http://z.about.com/d/compreviews/1/0/1/4/DIY-MB11.jpg">

Notice the color of the wires...that is an ATX standard. The voltages correspond to this:

ATX Voltage Specifications

Nominal Voltage

Wire Color


Minimum Voltage

Maximum Voltage



+5 V

Red

4.75 V


5.25 V



-5 V

White

-4.75 V

-5.25 V




+12 V

Yellow

11.4 V

12.6 V




-12 V

Blue

-11.4 V

-12.6 V



+3.3 V


Orange

3.135 V

3.465 V




="http://www.certiguide.com/apfr/diagrams/figure408.png">

source for handy chart and images

What you'll do to backprobe the power supply is to touch the black probe to bare, unpainted metal inside the case (do NOT touch any components), and the red probe will get jammed into the top of each connector on the harness, past the wire (red, orange, white, black, yellow etc).

BE CAREFUL not to touch either probe to anything other than black to bare metal, and red to wire harness. Doing so could destroy the machine.

When the red probe is in the respective hole (and black probe grounded to metal on the case), check the voltage reading on the multimeter, and compare it to the expected value in that chart.

The ATX spec allows a tolerance of +/- 5%, so if the result deviates from the spec by greater than 5% in either direction, you have a faulty power supply.

The grounds should not leak a significant amount of current...if you see a figure greater than .1 on a ground, it's considered leaky (and faulty).

The tricky thing is that power issues can be intermittent. Due to fluctuations in current from the wall, a subpar power supply could test fine if plugged into a good socket, but fail to do it's job when the current dips for a moment (like a momentary brownout). A "good" ATX power supply should handle this situation to a reasonable point, a failing one may not. As such, try to test this in place, or as close to the production situation as possible.

One last thing to know about power supplies. Not all watts are created equal. Just b/c the rating on the side of the PSU says "400 watts" doesn't necessarily make it so. There are variations in quality among PSUs, and in your typical BestBuy consumer PC, like a Presario or E-machine "crap"uter, the manufacturer may cheap out on the power supply. (Which makes sense, seeing as that's not something that's advertised in the Sunday circulars -- they hype the CPU, how much RAM, how much HD space, etc -- but not the quality of the PSU. They cheap out on it b/c they can.)

Here's an easy way to tell. If you're in a store comparing two PSUs, both are from reputable manufacturers, both are rated at the same wattage, both cost the same amount of money...which PSU should you choose? The heavier one. The one that weighs more will have better components under the hood, a heavier coil etc -- and will stand up better to the rigors of production. All else being equal, "buy power supplies by the pound".

Hope this is helpful!
posted by edverb at 8:46 AM on November 25, 2006

strange...the images and table worked in preview. Sorry about that.
posted by edverb at 8:47 AM on November 25, 2006