Harddisk problem

[Kevin Lam]

Hi experts,

A week ago when I was browsing the net, the computer suddenly shut
down, as if there is a power cut, it failed to power on.

My experience told me that it seems like a power surge causes either
the motherboard or power supply gone...

I changed the power supply but it still refuses to boot up. Then i
discovered that if i unplug the harddisk, it works perfectly.

What's the most likely cause of this problem? and how could i recover
the harddisk information??

Thx

Kevin

 

[[email protected]]

Hi experts,

A week ago when I was browsing the net, the computer suddenly shut
down, as if there is a power cut, it failed to power on.

My experience told me that it seems like a power surge causes either
the motherboard or power supply gone...

I changed the power supply but it still refuses to boot up. Then i
discovered that if i unplug the harddisk, it works perfectly.

By "Unplug," I assume you mean the power plug??? If the power refuses
to come up with the HD power leads attached, then the HD is drawing too
much current. Normally a new logic board for your HD would solve your
problem and allow you to retrieve the data.

If on the other hand you find the problem is the IDE cable and not the
power cable, it is probably also the logic board, but there is a VERY
slight chance the IDE cable is defective. Try a different IDE cable
before condemning the logic board of the HD.

 

[w_tom]

It fails to power up or fails to boot? The first tool a
computer repairman would use is the 3.5 digit multimeter.
Which critical voltage is not obtaining spec? Then that
missing voltage would cause the others to shutdown. Which
voltage is an important fact.

Apparently disk drive is shorting out one of the voltages.
However that short typically would cause a visually noticeable
indication.

Again, this assumes power failing - which was not directly
stated in the original post. Computer could simply fail even
though voltages are OK. Or disk drive could be loading power
supply to the hairy edge now causing failure. We don't have
definitive facts about power.

How to recover data? Well one system recently stopped
booting. Traced failure to a drive transistor on disk drive.
Eventually got that circuit repaired. All data, except one
file, recovered. Notice that first I identified failure. Only
then tried to fix it.

Experience tempered by how things work says surges are
rarely reason for failure. Most who blame surges are simply
speculating due to retail shelve propaganda; not because
electronic analysis is performed. Take this disk drive
transistor failure as example. If a surge causes this damage,
then many other things would have also been damaged. Failures
are more often attributed to manufacturing defects.

Drive data may be recoverable as I recently demonstrated.
From information posted, nothing can be definitively
identified as reason for failure. It is why analysis starts
with a 3.5 digit multimeter - and other important details.
Same detailed analysis demonstrates that most 'surge' damage
is based only in speculation. Surges are that rare and would
have damaged far more than one drive.

 

[Andre]

Hi experts,

A week ago when I was browsing the net, the computer suddenly shut
down, as if there is a power cut, it failed to power on.

My experience told me that it seems like a power surge causes either
the motherboard or power supply gone...

I changed the power supply but it still refuses to boot up.

I had a power supply fail like that, the vendor didn't want to know
but did tell me that my machine was likely to be OK as the modern PSUs
fairly well insulate the mainboard against power spikes if they aren't
too big.

Chances are that the spike has shorted a tantalum capacitor (little
black or yellow surface mount thing) on the drive's controller board,
this can be a single shot event with those. Good news is if you remove
the "bad" capacitor and the drive starts working, it should be
recoverable though don't trust it with unbacked-up data

I know of cases where replacing this one part has gotten the drive
working again and it has been fine for years afterwards.

-A
#include "Disclaimer.h"
#include "YMMV.h"

Then i

 

[Jef]

If your at a business with a lot of those computers go take the circuit
board off a similar hard drive. It works most of the time in this
situation. -jeff

 

[Hawkeye]

Don't eliminate the power supply just yet. It could be that it is
borderline and plugging in the HD puts it over the edge.

Try the drive and the PS in a different computer if possible, but not
at the same time...