HD/PD dead due to power surge

[Tim]

Hi,

There was a power surge and the power supply of the computer gave out.
The motherboard and CPU are dead, as are the 2 hard disks and the
CD-ROM/PD drive. I have no idea on the expansion cards...

All data was on those hard disks, with a (fairly old) backup on the PD
drive. For those that don't know a PD (phase-change dual) drive, the
cartridges can hold 650 MB and the technology can be compared to
DVD-RAM. I think I haven't seen those drives since 1998.

We lost all our data (especially my sister's thesis work), so apart
from a lot of broken hardware that I'll have to replace, I'd like to
recover the data from the HD's and the PD drive. One HD has a chip
burnt and doesn't spin anymore. The other does, but isn't recognised
by the BIOS.

I could send the HD to a data recovery lab, but unfortunately I don't
have that kind of money. I heard about putting the electronics of
another (similar) HD on the broken HD and copying everything. Has
anybody ever done this? Succesfully? Does similar HD mean exactly the
same? Are there any other things I can try?

Does anybody have an idea on the PD cartridge? Are there devices that
can read it and are still sold?


Thanks a lot for the help!


Cheers,
Tim

 

[JT]

Hi,

There was a power surge and the power supply of the computer gave out.
The motherboard and CPU are dead, as are the 2 hard disks and the
CD-ROM/PD drive. I have no idea on the expansion cards...

All data was on those hard disks, with a (fairly old) backup on the PD
drive. For those that don't know a PD (phase-change dual) drive, the
cartridges can hold 650 MB and the technology can be compared to
DVD-RAM. I think I haven't seen those drives since 1998.

We lost all our data (especially my sister's thesis work), so apart
from a lot of broken hardware that I'll have to replace, I'd like to
recover the data from the HD's and the PD drive. One HD has a chip
burnt and doesn't spin anymore. The other does, but isn't recognised
by the BIOS.

I could send the HD to a data recovery lab, but unfortunately I don't
have that kind of money. I heard about putting the electronics of
another (similar) HD on the broken HD and copying everything. Has
anybody ever done this? Succesfully? Does similar HD mean exactly the
same? Are there any other things I can try?

Does anybody have an idea on the PD cartridge? Are there devices that
can read it and are still sold?


Thanks a lot for the help!


Cheers,
Tim

Try Ebay and surplus outlets. PD is not being made as far as I know.

JT

 

[Tim]

Try Ebay and surplus outlets. PD is not being made as far as I know.

JT

Thanks for the tips. I haven't been able to find one yet. Even lending
one would be great, but few people seem to have heard of such a thing,
let alone have one...

Tim

 

[terry_b17]

Tim,
check out this article at
http://techrepublic.com.com/5100-6255-1053837.html
regarding the controller swap .
hope this helps,
terry

==============
Posted through www.HowToFixComputers.com/bb - free access to hardware troubleshooting newsgroups.

 

[JT]

Thanks for the tips. I haven't been able to find one yet. Even lending
one would be great, but few people seem to have heard of such a thing,
let alone have one...

Tim

Saw 2 on ebay today. Searched for PD optical and they came up. look quick
before they are gone.

PD was not a popular format, and is probably dying a well deserved death.

JT

 

[Tim]

Saw 2 on ebay today. Searched for PD optical and they came up. look quick
before they are gone.

I'm from Belgium, and couldn't find any on ebay.be (even when searching
worldwide). On ebay.com, som cartridges turned up, but no drive. Did you
use another URL or am I just too late?

PD was not a popular format, and is probably dying a well deserved death.

It wasn't popular, but the cartridges are far more reliable than
CD-ROM's, in my opinion.
I found a new MO drive (9.1 GB cartridges). I don't know if it's
backward compatible, but at 2300 euro it's not an option.


Thanks,
Tim

 

[Tim]

Tim,
check out this article at
http://techrepublic.com.com/5100-6255-1053837.html
regarding the controller swap .
hope this helps,
terry

==============
Posted through www.HowToFixComputers.com/bb - free access to hardware troubleshooting newsgroups.

Thanks Terry!

 

[w_tom]

First, you don't describe a failure from a power surge. You
describe a failure classic of a discount power supply that was
missing essential functions. If a power supply was selling
for $40 or less, then this type of failure is too common.

Try to replace the drive electronics board. Exact model
number must be know. There are plenty of disk drive
replacement companies that sell used drives. One used this
company to solve his failure:
www.computertradeexchange.com

These electronic boards are attached to disk often using
torque head bolts. Often using sizes that are less common.
Take the old drive dow to the hardware store to buy a torque
driver for those bolts.

Do not try to write to the rebuilt disk. Only read and copy
data from it. IOW don't even boot from the rebuilt disk.
Just another precaution.

Had power supply contained functions that were even defacto
standard in the 1970s, then the damage as you have described
just would not be possible. Those functions are routinely
forgotten when importing supplies intended only for the
technically naive clone computer assemblers. IOW also get
minimally acceptable power supplies next time. They typically
cost at least $60 retail. How to increase profits AND sell
power supplies at lower cost? Forget to include the long list
of essential functions in a power supply. One such function
would have made your current problem impossible.

 

[Odie Ferrous]

Tim,
check out this article at
http://techrepublic.com.com/5100-6255-1053837.html
regarding the controller swap .

Sorry, but some of the information Techrepublic have presented is not
correct.

It is rare that you will be able to recover a drive simply by replacing
the circuit board with that from a working drive.

This is often due to the fact that the circuitry tends to run right
along to the read/write heads inside the drive itself, so you would have
to replace those as well as the circuit boards. This is a lot more
difficult than it sounds.

TR then writes:

"TheChas also advised Mark on successfully retrieving the data. "To
recover data from a drive with a controller error, you need to find the
exact same model hard drive. Then, you need the aid of an electronics
tech with excellent soldering skills. Swap the electronics between the
working drive and the dead drive."

I have yet to see a "recent" drive where changing the electronics
(assuming the circuit board) requires soldering.


Odie

 

[Tim]

First, you don't describe a failure from a power surge. You
describe a failure classic of a discount power supply that was
missing essential functions. If a power supply was selling
for $40 or less, then this type of failure is too common.

Why does the power supply fry the internals if there's no power surge on
the input of the supply?

Try to replace the drive electronics board. Exact model
number must be know. There are plenty of disk drive
replacement companies that sell used drives. One used this
company to solve his failure:
www.computertradeexchange.com

Thanks, I'll check them out for sure!

These electronic boards are attached to disk often using
torque head bolts. Often using sizes that are less common.
Take the old drive dow to the hardware store to buy a torque
driver for those bolts.

I should have most, but will check, thanks.

Do not try to write to the rebuilt disk. Only read and copy
data from it. IOW don't even boot from the rebuilt disk.
Just another precaution.

Good idea, I didn't think of that.

Had power supply contained functions that were even defacto
standard in the 1970s, then the damage as you have described
just would not be possible. Those functions are routinely
forgotten when importing supplies intended only for the
technically naive clone computer assemblers. IOW also get
minimally acceptable power supplies next time. They typically
cost at least $60 retail. How to increase profits AND sell
power supplies at lower cost? Forget to include the long list
of essential functions in a power supply. One such function
would have made your current problem impossible.

I will. How can one check? Price is a nice indication, but with my luck
I would end up being screwed over twice


Thanks,
Tim

 

[Tim]

Sorry, but some of the information Techrepublic have presented is not
correct.

It is rare that you will be able to recover a drive simply by replacing
the circuit board with that from a working drive.

This is often due to the fact that the circuitry tends to run right
along to the read/write heads inside the drive itself, so you would have
to replace those as well as the circuit boards. This is a lot more
difficult than it sounds.

Couldn't it be that that made it? One of both disks still spins up, the
other doesn't. The important data was of course on the one that doesn't
spin up. It could mean the motor is dead (no joy), but if it's
electronics, I still don't know where that would be (in- or outside).
Any idea?

TR then writes:

"TheChas also advised Mark on successfully retrieving the data. "To
recover data from a drive with a controller error, you need to find the
exact same model hard drive. Then, you need the aid of an electronics
tech with excellent soldering skills. Swap the electronics between the
working drive and the dead drive."

I have yet to see a "recent" drive where changing the electronics
(assuming the circuit board) requires soldering.

Well, I for one hope it doesn't ;-)


Thanks a lot,
Tim

 

[w_tom]

Power supply circuits on far side of transformer drive
(output) more power through transformer in response to a low
voltage indication. But what happens when the voltage
indicator circuit (on near side of transformer) fails; does
not report full voltage? The driver circuits attempt to
output more power - to up DC output voltage. As the 5 volts
climbs above 7 volts, then digital ICs (such as those on disk
drive) fail. This is only one reason why all minimally
acceptable supplies contain a special and independent circuit
- that shorts out the 5 volts should it exceeds 6.3 volts.
Circuit is called overvoltage protection. Many if not most
clone power supplies forget to include that required circuit.
Then many naive computer assembler assumes it is normal for a
power supply to damage motherboard and disk drive; rather than
first learn basic electrical technology.

Power surge had nothing to do with this failure scenario.
For that matter, read power supply specs. Typically it should
withstand even 2000 volts common mode surge without damage.
Power supplies already contain effective protection.
Protection that can be effective inside or adjacent to the
computer should already be inside the supply.

 

[Tim]

Could you suggest some texts about the criteria for power supplies and
how to test them?


Thanks,
Tim

 

[w_tom]

What do you want to test for? That it is functional
(Go-Nogo test) or something more comprehensive. Do you want
to test the many functions of that supply? Do you want to
test for reliability? IOW what is the purpose of your
testing? - a question that must be answered before an
appropriate test can be recommended.

Any serious power supply test will require full loads - ie
resistors chained together to make maybe what - 400 watts?
3.5 digit or better multimeters. An oscilloscope. Variac to
run supply under various input voltages. Etc. Are you ready
for all this?

Why does Toyota have legendary quality? They don't test and
don't inspect. This may be a concept not yet understood. But
first we need to understand why you want to test - what is the
objective of that testing?

As for texts on how power supplies work: I once needed
formulae for the design of low pressure inert gas tubes.
Problem is the technology is so old and well proven that books
today no longer teach those basics. Same with power
supplies. Best I can recommend is a college library (that has
electrical and electronic courses) where the library existed
well before 1980. Or learn concepts from data sheets for
power supply controller ICs. Texas Instrument, Linear Tech,
National Semi, and Maxim Semiconductor are but a few
suggestions. Electronic Design, Electronic Products, and EDN
magazine have had articles on power supply basics.

 

[Tim]

Hi,

A functional test is interesting, especially if it tests whether the
power supply would shut off in case of a power surge. Maybe this means
testing for reliability as well?
Basically I want to make sure that a given power supply won't destroy
anything (as far as that's possible).

What you wrote about the electrical tests, I'm not ready for all of
that. I've got a multimeter, but have little use for an oscilloscope and
testing a few power supplies doesn't really justify the purchase.

Maybe if Toyota makes sure the variation in their production process is
(nearly) zero, there's no reason to test.

Thanks for the tips on the reading material.


Cheers,
Tim

 

[w_tom]

The reason why Toyota does no incoming inspections or
testing is due to statistical process control. A concept
beyond the scope of this discussion - other than one should
not have to test any power supply before installing it.

Previously posted are procedures to verify a power supply
with a multimeter. Major reason to perform this test is to
learn. Learn how a supply works (including signal
communications with motherboard controller), and how to locate
or eliminate a component as reason for failure:
"Computer doesnt start at all" in alt.comp.hardware on 10
Jan 2004 at http://tinyurl.com/2t69q and
"I think my power supply is dead" in alt.comp.hardware on 5
Feb 2004 at http://tinyurl.com/yvbw9 .

Another reason why testing is not sufficient for quality is
that many functions cannot be tested. Example: overvoltage
protection. Overvoltage protection cannot be tested which is
why the supply must provide a long list of specs stating what
really is provided internally. No user testing can confirm
that function. Customer must select vendor with appropriate
attitude and knowledge - essential factors for quality.

 

[Tim]

Hi Tom,

thanks for all the great replies, I really appreciate it!

Now I'm going to read some ;-)


Cheers,
Tim