Fixing a computer that was 'struck' by lightning

Subterranean

Subterranean

Subterranean

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Just been helping my girlfriend with her computer that was in sleep mode when the power has hit by lightning this morning. It seems to have taken out her router, but also the computer.

When pressing the on button, nothing happens, however the LED on the motherboard is lit up. We have tried a working power supply with exactly the same problems so it doesnt seem to be just the power supply. Is it likely going to need a motherboard replacement? and if so, how likely is it that other things have been taken out too, memory etc?

We tested the power supply on its own by shorting the pins on the ATX connector, and it powered up fine.

Is it possible, given that the router went down too, that the surge may have come through the phone line and through the ethernet cable from the router?

Any help is appreciated.
 
yes would be the answer to your question it is very likely the pc has ben fired by the surge coming from the router throught the ethernet cable.
I have had this before as well and was quite lucky as all it took with it was the mobo

what you need to do is test each bit of hardware one by one if you can and hope its not taken the whole pc out with it

what i would also sugest is a surge adapter that also protests the phone line as well as the rj45 socket as well
after my experince that what i did and touch wood (knocks head) it wont happen again
 
Possible that it will have come down the phone line as well.

Surprised the psu is still working. Anyway it does indeed sounds like the mobo is fubar.

However, check the mobo by removing everything that is not necessary and just with one ram chip. Even try it without the graphics card as although there will be nothing on the screen, you will be able to tell if it boots up.

It just might be something else which is connected into your mobo which has gone fubar and stopping the pc from booting up.

The bad news is that I have seen pcs from lightning strikes where it has taken out the psu, mobo, memory, and graphics card.
 
Check the northbridge and southbridge chips for any pops or bubbles. They tend to go if the board has gone.
 
testing one by one is a good idea, inc testing components in a known good mobo. Just make sure it's a spare. Not sure how a pc mobo might react to a dead short on say a ram module.

However i'd say the whole lot is shot, claim off house insurance. Even if bits still work a lightning strike can damage components which then fail later.

We use to repair ty's which repeatedly bounced back into the work shop. Only after 3rd repair did we find out from customer that they had a strike nearby.
 
Might be worth checking your household insurance :)

There's someone who I'm "tech support for" (they're 80 bless them) and their old Dell laptop, they'd been given 29th hand and was literally worth peanuts, got struck by lightening through the phone line..... insurance gave them the original purchase price to go and buy a new one with.
 
Bloke at work also clamed on his house insurance. Went out brought a new pc. Phoned them to see if he could claim they just said send the recipt and they would refund him.
 
Hi I've got a pretty dumb question, what was the source from which the PC was struck? you got the pc connected to the outside TV aerial or something? probally the daftest question ever but just wondering.

If I've just got Virginmedia cable modem connected, not much chance of being struck is there???
 
Subterranean said:
We tested the power supply on its own by shorting the pins on the ATX connector, and it powered up fine.
Is it possible, given that the router went down too, that the surge may have come through the phone line and through the ethernet cable from the router?
Click to expand...
That test implies the power supply controller or some other functions of the power supply 'system' are harmed. For example, is the power switch still 'talking' to the controller?

To have damage, the surge current would be incoming on something and outgoing to earth via something else. In many nations, the phone line routinely earths a 'whole house' protector. Therefore the phone line is the outgong path to earth. So, what was the incoming path that would have passed through that power controller? Only one or some things in that path would be damaged. Knowing that path identified damaged parts AND overstressed parts. Overstress is a failure that occurs days or weeks later.

Memory would have an incoming path. But where is the outgoing path? Therefore memory would not be damaged.

Is it the controller? Measuring the green wire from motherboard to power supply both before and when the switch is pressed would say something useful. Tracing the actual surge path requires identifying the outgoing path to earth - to identify everything that was in a path from cloud to earth. Then only those items need further consideration.
 
a bit off topic, but the lightning doesn't have to hit, say a phone line for your phones to break, just has to be in a certain radius.
had a lightning storm at my house only a few weeks ago, which took out the router,house phones (only the portable ones), tv's, sky box and fried the lnb on the sat dish, all in 1 hit in the field next to the house.
the fact that a lightnig strike is so harmfull to all the electronics in the house is that fact that when the lightning hits the ground ( simple explanation ) the ground around the strike is live. now what is the only thing that wires to the ground, o the earth wire. so everything in your house can become live from the ground wire. so during a strom its best to unplug everything, even if you have a surge, the surge only protect up to certain voltages, so when the a couple of hundred thousand to a million volts come up the earth wire its not gonna be that usefull.

in regards to the pc i think you should try and claim from the insurance, after you have tried testing your components. but if you think theres no point or not worth it just put in a claim.
 
I had the same thing on the day of a thunder storm. Came home the computer fans were running but the computer not, it was turned off before i went to work!
On swopping parts found two ports on router fried, psu and motherboard fried rest was fine!
 
Everyone with any electric devices should invest in surge protector strips.

On another note, why do they even bother making the standard power strips without the surge protection? Mine only cost me £4 more for a decent belkin one.
 
Having previously worked for a company where one of the contracts was checking out computers for an insurance company, I can only second what people are saying here about contacting your home insurance company.

I've seen pc's where simply replacing a PSU or dial-up modem fixed the fault, but on the other hand I've seen pc's where every single component in the machine is fried. Also just replacing an obviously faulty component now might not mean something else has been damaged/stressed and fails in a week/month/year as a direct result of the surge and you wouldn't be able to make a second claim for the same incident.

Surge protectors can help if it's a distance strike, but close or direct to your property nothing will help short of disconnecting everything.
 
weegill said:
a bit off topic, but the lightning doesn't have to hit, say a phone line for your phones to break, just has to be in a certain radius.
Click to expand...
Which is why BT often has whole towns without phone service for four days while they replace the damaged computer.

Not really off topic. Better is to learn why that damage was a direct strike. For example, lightning struck a tree some 20 meters from a cow. The cow died. Lightning is an electrical connection from cloud to earthborne charges so 6 kilometers distant. Shortest electrical path was 3 kilometers down to the tree, through earth, up the cow's hind legs, down its fore legs, then onward another 4 kilometers to those charges. Cow was in a direct connection from cloud to earthborne charges.

If making conclusion only using observation, one would conclude EM fields from a nearby lightning bolt killed the cow. Nonsense. That cow conducted an electric current that took a shortest electrical path.

Same applies to household appliance damage when earthing is improperly installed or does not even exist. A cow standing inside a buried wire loop would have survived. That cow violated the ‘single point ground’ principle.

This example also explains household electrical damage. (And why humans are advised to keep feet together during thunderstorms).

Same concept is why surge protection is installed when the footing are poured. Ufer grounds (rather than grossly overpriced plug-in protectors) are one solution to superior surge protection. Humans have ‘set up’ a building for damage if all utilities do not enter at a common location (service entrance) and do not make a short (ie 'less than 3 meters') connection to a best earthing electrode.

It's all about the current path. A building with a superior single point earth ground is equipotential. Voltage everywhere in a building rising by 5,000 volts means near zero voltage differences. No outgoing path means no current. No current inside the building means no damage. (BTW, concrete footings are a better conductor of electricity. And further enhance surge protection if rebar is properly installed.) Damage (even to the cow) is about a path from cloud to distant charges.

Destructive nearby fields are a popular myth not supported by fundamental science. If nearby fields are destructive, then every mobile and car radio (connected to something to maximize those EM fields) would be damaged with every nearby strike. That 'nearby strike' myth is contradicted by facts, numbers, and examples.

One should learn from the damage. What was the incoming and outgoing path through damaged electronics? That damage occurred because the nearby strike caused current to flow inside the building. Damage directly traceable to human failure. Destructive electricity occurs when current flows through electronics - the always required incoming and outgoing path.

Why does BT not have damage from nearby strikes? These concepts are so well proven these past 100 years. Just another example of why surge protection is always about earthing.
 
sturmtruppe said:
On another note, why do they even bother making the standard power strips without the surge protection?
Click to expand...

Because power strip protectors do not even claim to provide that protection?

If you disagree, then post those manufacturer's numeric specifications that list each type of surge and protection from that surge. You cannot. No power strip protector claims such protection.

Worse is a problem seen by most fire departments. Scary pictures and even a description of why that failure occurs:
http://www.hanford.gov/rl/?page=556&parent=554
http://www.westwhitelandfire.com/Articles/Surge Protectors.pdf
http://www.ddxg.net/old/surge_protectors.htm
http://www.zerosurge.com/HTML/movs.html
http://www.tiny url.com/3x73ol (without the space)
http://www3.cw56.com/news/articles/local/BO63312/
http://www.nmsu.edu/~safety/news/lesson-learned/surgeprotectorfire.htm
http://www.pennsburgfireco.com/fullstory.php?58339

Where does that energy get dissipated? If the protector connects to earth, then a surge is harmlessly absorbed there. If the protector has no place to *divert* hundred of thousands of joules, then what happens? Sometimes those scary pictures.

Surges are an electric current from cloud to earthborne charges. If that current gets connected to earth before entering a building, then no damage. Protection inside every appliance is not overwhelmed. But if not earthed, then a surge will go hunting for earth ground, destructively, inside the building.

Nothing stops a surge. The NIST (US government research agency) says what a protector does:
> A very important point to keep in mind is that your
> surge protector will work by diverting the surges to
> ground. The best surge protection in the world can
> be useless if grounding is not done properly.

What does a power strip not have? What is necessary to make a 'low impedance' connection to earth? Short (ie 'less than 3 meters') connection to single point earth ground. No sharp wire bends. No splices. Separated from non-grounding wires. Not inside conduit. Power strip protectors have all but no earth ground. Too much honesty would harm sales. So its manufacturer also avoids all discussion about earthing. And does not claim to provide protection in numeric specs.

Just a few reasons why spending £4 for the more expensive protector provides little useful, can even create scary pictures, and may even earth that surge destructively through an adjacent appliance.

What does BT do? Connected to overhead wires all over town, how does BT have no damage? Do they disconnect phone service during every thunderstorm? Simple. Protectors earth every wire where it would enter the building (at earth ground) and up to 50 meters from electronics. That separation between protector and electronics increases protection.
 
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Thanks to everyone who replied to this to help me. We were away for the weekend but got it fixed today. Thankfully it was just the motherboard, everything else was absolutely fine. The router will be replaced by Be for free. It does seem like the surge came through the ethernet rather than the power in this case.

I've never had or known anyone who has had a computer taken out by lightning so we live and learn. A surge protector has been bought that includes ethernet/phoneline protection :)
 
I've been in the same boat as you before, the lightning took out my router and sound card, everything else was fine, its actually happened to me twice, I think someone up there hates me hahah
 
Subterranean said:
I've never had or known anyone who has had a computer taken out by lightning so we live and learn. A surge protector has been bought that includes ethernet/phoneline protection
Click to expand...
In the UK is almost zero lightning. So infrequent that virtually nobody should have lightning damage.

If the surge entered via the router, then you earth a protector where that signal wire enters the building - connecting within meters to earth. And if the surge was incoming via that path, then what was the outgoing path to ground? Or did it enter on AC mains and find earth ground through the ethernet router?

Either way, you imply the surge protector is a plug-in type. Now view its numeric specs. It does not claim to provide surge protection from typically destructive surges - such as yours. Don't take my word for it. Post those numeric specs.

A protector without a short connection to earth will even earth surges destructively through adjacent appliances. So ineffective (and obscenely overpriced) surge protectors do not claim protection from each type of surge AND avoid all discussion about earth.

A surge was permitted inside your building. Effective protection means no surge energy must enter the building. But in the UK, you have almost no surges (of course your location could be uniquely different). So a protector that does not claim any protection may be more than sufficient. Since you would have the same or even better protection without that 6 quid protector.
 
What do you suggest as an alternative? About the only solution I can see is a direct link to earth which needs at least 260V to conduct, so during normal operation it has no effect but when a large surge comes through the mains ac it takes the path of least resistance through this device.

Something that connects the mains ac to the house plumbing through this device would seem like a winner, since you can pass enormous amounts of electricity through water filled 22mm pipe, and the resistance would be low.

I can't think how one could implement this, so Id be interested as to your thoughts.

To the post ages ago about cows near a tree being killed, the bbc reported on it a while ago. They thought the large puddle they were all standing in was the cause, all the cows under the tree were killed not just one.
 
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