Post power surge problems

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Hello all,

As some of you may know there was a lightning storm in England
recently. The power went out for a second and my PC which was
connected to a Cyberpower BR-650E surge protector and UPS lost power.
Somehow the surge protector and UPS was not able to protect the PC.

I rebooted and the BIOS said the motherboard detected a power surge.
On entering Windows everything seemed to be fine so I went to bed.

The following morning I could not enter Windows 7 (blue screen) or
SuSE Linux 11.3 (something about a recursive error). When I tried
using a Windows 7 installation DVD, it blue screens on "Loading

Clearly some hardware has been damaged by the power surge. Should I
buy a replacement PSU, motherboard, CPU, graphics card or RAM?

I use the computer as my main PC in a SOHO and really need it up and
running ASAP.



Re: Post power surge problems

J B wrote:
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The good news (if there is any), is that a lot of stuff is
working on your computer. If you're seeing a BIOS screen,
and not badly scrambled, lots of stuff had to work
for that to show up.

For the sake of completeness, I'd run memtest86+.
You can get that from , half way down the page.
Disconnect all storage devices, except whatever storage device
will be used to boot memtest86+. This is to prevent broken storage
devices from upsetting the BIOS.

If you have one stick of RAM, the bottom 640K can't be tested.

If you have two sticks of RAM, pull them, then reinsert them
in "single channel mode". One stick will be the "high memory"
stick, and fully tested. The second stick will be the "low memory"
stick, and it's bottom 640K won't be tested. Run one pass of memtest86+
error free, before continuing.

Then, swap the sticks in their two slots. This makes the low address
stick the high one. And then it will be completely tested.

If you owned four sticks, repeat the procedure using only the two
remaining sticks.


If that passes, my real suspicion, is something happened to the disks.

Do you have backups ?

Was the backup drive disconnected during the lightning storm ?

Backups should be disconnected when not in use. This reduces the chance
they'll be burned by lightning.

If you have access to a second computer, connect the drive(s)
from the damaged computer, one at a time. You could also bring
over the optical drive, and test it.

Your first test, would be a read-verify, to prove the sectors
are all accessible. While a natural reaction would be to reach
for CHKDSK to do this, the thing I don't like about CHKDSK, is
it is a "repair-in-place" tools. If you had an IDE cable on the
drive, and the cable was bad, CHKDSK has been known to trash
a disk, because each write attempt fails due to the bad cable.
CHKDSK works best, if the disk is actually healthy, and all
that was needed, was rewriting some structures.

If you don't have backups, you can even consider backing up the
damaged drives. And in the process, the backup tool may complain
about bad sectors. The backup procedure (sector by sector) then
functions as the "read-verify test".

So my first purchase, might be some replacement drives, which will
function quite nicely in the first ten minutes of your experiments,
as your backup destination when you copy the questionable disks.

With backups in hand (sector-by-sector in case the file system(s)
are damaged), now it's "safe" to use CHKDSK. If CHKDSK makes
noodle soup out of the drive, you have your backup to restore with.
And if the backup attempt failed, you also get evidence of
a hard drive failure. (Then the disks purchased, become your
new blank disks for OS reinstallation.)

For home repair work, a second computer is very convenient. It's
pretty hard to (cheaply) repair a single PC, while commuting to
the public library to use their machine to Google stuff :-)
And in this case, a second machine, with disk interfaces
suitable for testing your storage devices, would be
an excellent tool to have access to.


In terms of resilience to power surges:

1) A cheap ATX supply ($20) can have virtually no protection features.
    A transient could come right though it. The surge protection on
    a UPS, may still let dangerous transients through.

2) The motherboard has switching converters on it. These provide
    a measure of buffering on transients. The processor has the
    Vcore switcher (and that protects the processor). System RAM has its
    own little one or two phase supply (providing a measure of protection).
    This is a potential reason the CPU and RAM will survive, even if the
    motherboard is blown. (And we don't have any symptoms yet, which
    positively verify a bad motherboard.)

3) Hard drives, have something like an MOV across +5V and +12V to ground.
    They're on the disk controller board, near the power connector.
    This suppresses transients. A continuous power surge (for many seconds)
    will cause the protection devices to burn. The MOV like device is not
    intended to protect against a continuous surge. Only a pulse of too
    much voltage gets stopped. The +12V one, may clamp at around 15V or so.

    The disk cabling is susceptible to induced currents. So the interface
    on a drive could be ruined.

I haven't read of enough surge cases, to rate all of these possibilities.
The CPU and RAM do seem to hold up very well. The reason I'm having you
test the RAM above, is because RAM naturally goes bad on its own, and
if you haven't tested it within the last year or so, it's time to test it
now and find out if it is still good. I don't think the transient event
got it. But it could still be bad. Then the next step, is testing
disks and optical drive, one at a time, on another computer. Making
backups etc.

If you get any more new interesting symptoms, post back.


Re: Post power surge problems

Hi Paul,

Thanks for your very helpful reply!

The fried PC has 3 hard drives, 2 of which are encrypted with
Bitlocker. I pulled out the main drive (unencrypted) and tested it
with a IDE/SATA -> USB adapter and it seemed to be fine. I didn't test
the encrypted drives because it would have been irrelevant to the
Windows 7 login or re-installation blue screens.

I've ordered a new Socket AM3+ motherboard.

Will run Memtest overnight. In my experience Memtest hasn't shown up
problems before. A previous PC had an undocumented incompatibility
between munchkin RAM and the motherboard and kept blue screening.
Memtest kept on testing perfectly. Changing the RAM fixed the BSODs.

Just when I am busiest with work the PC gets trashed by lightning!

Paul wrote:
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Re: Post power surge problems

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Do you mena the fried drives aren't even recognized when the computer
powers on, in the BIOS screen?  If so, the drives  or the
motherboard's controller really is fried.  Otherwise you may want to
see what the drive makers' self-booting SMART diagnostic says because
a lot of times a power surge just causes cached data to be lost.

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Don't use Memtest because it's a fairly lousy diagnostic.  MemTest86,
MemTest86+, and Gold Memory are better, and I'd prefer to run Gold and
one of the other two tests because the combination almost always finds
errors in overnight testing.  But test for a long time because  I've
had errors not appear for 4-5 hours, and one person saw nothing with
MemTest86+, while Gold revealed an error in about an hour but neede
another 9 hours to show it again.

Re: Post power surge problems

On 6/18/2012 6:40 PM, westom wrote:
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Some protectors even have protected equipment warranties.

Excellent information on surges and surge protection is at:
- "How to protect your house and its contents from lightning: IEEE guide
for surge protection of equipment connected to AC power and
communication circuits" published by the IEEE in 2005 (the IEEE is a
major organization of electrical and electronic engineers).
And also:
- "NIST recommended practice guide: Surges Happen!: how to protect the
appliances in your home" published by the US National Institute of
Standards and Technology in 2001

The IEEE surge guide is more technical. Both are based on US wiring
practice, but the principles are the same everywhere.

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The author of the NIST surge guide investigated how much energy might be
absorbed in a MOV in a plug-in protector. Branch circuits were 10M and
longer, and the surge on incoming power wires was up to 10,000A . (That
is the maximum that has any reasonable probability of occurring and is
based on a 100,000A strike to a utility pole adjacent to the house in
typical urban overhead distribution.) The maximum energy at the MOV was
a surprisingly small 35 joules. In 13 of 15 cases it was 1 joule or less.

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Service panel suppressors are a real good idea.
But from the NIST surge guide:
"Q - Will a surge protector installed at the service entrance be
sufficient for the whole house?
A - There are two answers to than question: Yes for one-link appliances
[electronic equipment], No for two-link appliances [equipment connected
to power AND phone or cable or....]. Since most homes today have some
kind of two-link appliances, the prudent answer to the question would be
NO - but that does not mean that a surge protector installed at the
service entrance is useless."

Service panel protectors do not by themselves prevent high voltages from
developing between power and phone/cable/... wires. The NIST surge guide
suggests most equipment damage is from high voltage between power and
signal wires.

In England a phone entry protector often does not limit the voltage on
the wires to the earthing system as is common in the US. That is a
particular hole in surge protection for anything connected to power and

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Some equipment has some protection. Some has none. Not likely any has as
good protection as a plug-in protector.

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Not for a properly wired protector.

When using a plug-in protector all interconnected equipment needs to be
connected to the same protector. External connections, like phone, also
must go through the protector. Connecting all wiring through the
protector prevents damaging voltages between power and signal wires.

Would seem unlikely a surge got past 2 devices. Plug-in protectors are
likely to have higher ratings than UPSs.

Often power surges short the line side diodes in a computer power
supply, and sometimes blow the fuse. Often the computers work when those
components have been replaced.

On first reboot "BIOS said the motherboard detected a power surge" seems
like an odd message.  I don't know how BIOS would know. Lot of good
advice in the thread. Will be interesting if a new motherboard fixes the

Re: Post power surge problems

On 6/21/2012 9:39 AM, westom wrote:
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My only association with the surge protection industry is I am using
some surge protectors.
If westom had valid technical arguments he wouldn't have to lie.

My "subjective myths" come from the IEEE and NIST surge guides.

The correct link for the NIST surge guide, by the way, is:

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Westom googles for "surge" and is here because the OP said the magic
word. Westom is on a crusade to save the universe from the scourge of
plug-in protectors and compulsively posts his drivel all over the internet.

"Well proven science and experience" are in the IEEE and NIST surge
guides. Both say plug-in protectors are effective.

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Westom ignores that newsman also said "they gave me a ton of crap,
including that it was null and void b/c the Tivo was also connected to
the coax line for cable"

As both surge guides and my first post say, "external connections, like
phone [and cable], also must go through the protector". That is
essential in order to limit the voltage between all the wires. It is
inconceivable that Belkin did not say the same thing in instructions for
use. The claim was denied because of Newsman's incompetence. Westom does
not understand because of his incompetence.

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Then why did westom compulsively post his drivel about plug-in protectors?

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Anyone with minimal mental abilities can discover what the IEEE guide
says in this example:
- A plug-in protector protects the TV connected to it.
- "To protect TV2, a second multiport protector located at TV2 is required."
- The illustration "shows a very common improper use of multiport
- In the example a surge comes in on a cable service with the ground
wire from cable entry ground block to the earthing system at the power
service that is far too long. In that case the IEEE guide says "the only
effective way of protecting the equipment is to use a multiport
[plug-in] protector."
- westom's favored power service protector would provide absolutely NO

It is simply a lie that the plug-in protector in the IEEE example
damages the second TV.

For real science read the IEEE and NIST surge guides. Excellent and
reliable information on surge protection. And both guides say plug-in
protectors are effective.

Re: Post power surge problems

On 6/23/2012 8:51 AM, bud-- wrote:
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Looks like they moved it. This one works:
< !.pdf>

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