Guest
Most likely an inverter failure.
..
..
J
Jeff Liebermann
Guest
On Mon, 26 May 2014 05:06:15 +0000 (UTC), Calia <calia@its.invalid>
wrote:
Thanks.
It's not impossible to do SMT repairs, but it does help to have the
right equipment and plenty of practice. Also, if you're replacing
parts, it might be helpful to have a supply of known good
replacements. Cannibalism from other motherboards works in
desperation, but is not a good idea. I use a Chinese hot air SMT
workstation that I bought cheap on eBay for about $80. Make sure you
get a good selection of nozzles. The video you mentioned should have
had some aluminum foil around the chip to prevent the hot air from
melting nearby parts and plastic.
While this may be above your present abilities, I suspect that
throwing money at the laptop is not going to work because it will
probably cost as much as the laptop is worth to fix it. Big and
awkward 17" laptops, with only 1600x900 displays and a slow CPU, are
not exactly in demand. In the past, I've removed the motherboard, and
sent it off to a random reballing service:
<www.ebay.com/sch/i.html?_nkw=g72+motherboard+repair+service>
It usually cost me about $150 plus about $20 shipping each way. Add 2
hrs of my labor to tear it down, and put it back together, and I'm
well over the value of the machine.
It's unlikely to be the CPU. I haven't seen a dead Intel CPU for
maybe 10 years, and only a few older AMD Athelon chips that blow up
when the heat sink is dislodged. The CPU is in a socket so you can
easily replace the CPU. Photos:
<http://www.ascendtech.us/hp-615849-001-g72-series-motherboard_i_mbhp61584901g72.aspx>
The big white socket is for the CPU, which appears to be an Intel
2.0GHz P6100. Cheap.
<www.ebay.com/sch/i.html?_nkw=Intel+P6100>
From your detailed description (thanks), it looks like 1 flash, which
means "CPU not functional". More likely, it's one of the other chips
holding down the address or data lines causing the CPU to misbehave. I
can't tell from here which chip without poking my scope onto the
address and data lines.
One thing you can do is buy|borrow|steal a hot air SMT workstation and
get some practice on this machine. Well, practice on some old boards
first to get a feel for how much heat is needed and for how long.
However, don't try to remove the chip. Just slop on a mess of paste
flux, and heat it until the solder reflows. Maybe push LIGHTLY on the
chip to get it closer to the PCB. If the astronomical signs are in
your favor, you might end up with a usable board. If not, you won't
be any worse than you started, and maybe you can do better on the next
motherboard. Or just use it as a cat warmer:
<http://www.11junk.com/jeffl/pics/drivel/slides/Cat-warmer.html>
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
wrote:
Thanks.
It's not impossible to do SMT repairs, but it does help to have the
right equipment and plenty of practice. Also, if you're replacing
parts, it might be helpful to have a supply of known good
replacements. Cannibalism from other motherboards works in
desperation, but is not a good idea. I use a Chinese hot air SMT
workstation that I bought cheap on eBay for about $80. Make sure you
get a good selection of nozzles. The video you mentioned should have
had some aluminum foil around the chip to prevent the hot air from
melting nearby parts and plastic.
While this may be above your present abilities, I suspect that
throwing money at the laptop is not going to work because it will
probably cost as much as the laptop is worth to fix it. Big and
awkward 17" laptops, with only 1600x900 displays and a slow CPU, are
not exactly in demand. In the past, I've removed the motherboard, and
sent it off to a random reballing service:
<www.ebay.com/sch/i.html?_nkw=g72+motherboard+repair+service>
It usually cost me about $150 plus about $20 shipping each way. Add 2
hrs of my labor to tear it down, and put it back together, and I'm
well over the value of the machine.
It's unlikely to be the CPU. I haven't seen a dead Intel CPU for
maybe 10 years, and only a few older AMD Athelon chips that blow up
when the heat sink is dislodged. The CPU is in a socket so you can
easily replace the CPU. Photos:
<http://www.ascendtech.us/hp-615849-001-g72-series-motherboard_i_mbhp61584901g72.aspx>
The big white socket is for the CPU, which appears to be an Intel
2.0GHz P6100. Cheap.
<www.ebay.com/sch/i.html?_nkw=Intel+P6100>
From your detailed description (thanks), it looks like 1 flash, which
means "CPU not functional". More likely, it's one of the other chips
holding down the address or data lines causing the CPU to misbehave. I
can't tell from here which chip without poking my scope onto the
address and data lines.
One thing you can do is buy|borrow|steal a hot air SMT workstation and
get some practice on this machine. Well, practice on some old boards
first to get a feel for how much heat is needed and for how long.
However, don't try to remove the chip. Just slop on a mess of paste
flux, and heat it until the solder reflows. Maybe push LIGHTLY on the
chip to get it closer to the PCB. If the astronomical signs are in
your favor, you might end up with a usable board. If not, you won't
be any worse than you started, and maybe you can do better on the next
motherboard. Or just use it as a cat warmer:
<http://www.11junk.com/jeffl/pics/drivel/slides/Cat-warmer.html>
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
J
Jeff Liebermann
Guest
On Mon, 26 May 2014 06:53:56 +0000 (UTC), Calia <calia@its.invalid>
wrote:
>1. Cover all fan ports & run the PC hot for 20 minutes.
The theory is that since the BGA chips use low temperature (bismuth)
solder balls, it doesn't take much heat to reflow the solder. The
reality is that without flux, the broken solder connections are
unlikely to fuse together.
>2. Disassemble & reheat specific chips (e.g., cpu).
The CPU is in a socket. Buy a cheap replacement on eBay and try it.
>3. Disassemble & bake motherboard in the kitchen oven.
That will melt all the plastic parts (i.e. connectors). Bad idea.
There's a 4th option. Send it to someone with the expertise and
equipment.
<www.ebay.com/sch/i.html?_nkw=g72+motherboard+repair+service>
Just watch your costs very carefully.
>None seem particularly safe.
Well, they're a step above the Xbox repairs that use a sterno can
under the PCB to reflow the solder.
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
wrote:
>1. Cover all fan ports & run the PC hot for 20 minutes.
The theory is that since the BGA chips use low temperature (bismuth)
solder balls, it doesn't take much heat to reflow the solder. The
reality is that without flux, the broken solder connections are
unlikely to fuse together.
>2. Disassemble & reheat specific chips (e.g., cpu).
The CPU is in a socket. Buy a cheap replacement on eBay and try it.
>3. Disassemble & bake motherboard in the kitchen oven.
That will melt all the plastic parts (i.e. connectors). Bad idea.
There's a 4th option. Send it to someone with the expertise and
equipment.
<www.ebay.com/sch/i.html?_nkw=g72+motherboard+repair+service>
Just watch your costs very carefully.
>None seem particularly safe.
Well, they're a step above the Xbox repairs that use a sterno can
under the PCB to reflow the solder.
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
P
Paul
Guest
Calia wrote:
If you're serious about doing that, *don't* use the
oven that you use to prepare food.
Find a used toaster oven, keep it outdoors while
attempting the repair. The stink of melted plastic or
burned materials will stay with your used toaster oven,
while the family food oven is kept safe.
In an industrial setting, the duration (hold time) and
temperatures are all strictly controlled.
http://www.ami.ac.uk/courses/topics/0225_wave/images/ass_bapws_imgb.gif
As the posters note in your article above, if you heat the
entire motherboard, the electrolytic capacitors could
suffer. This is why a real re-work station uses a hood,
so the hot air only goes to the chip being repaired. If you
own a hot air gun, you can make a home made hood out of sheet
metal. For temperature monitoring, you could use a
thermocouple connected to a multimeter.
http://en.wikipedia.org/wiki/Thermocouple
Paul
If you're serious about doing that, *don't* use the
oven that you use to prepare food.
Find a used toaster oven, keep it outdoors while
attempting the repair. The stink of melted plastic or
burned materials will stay with your used toaster oven,
while the family food oven is kept safe.
In an industrial setting, the duration (hold time) and
temperatures are all strictly controlled.
http://www.ami.ac.uk/courses/topics/0225_wave/images/ass_bapws_imgb.gif
As the posters note in your article above, if you heat the
entire motherboard, the electrolytic capacitors could
suffer. This is why a real re-work station uses a hood,
so the hot air only goes to the chip being repaired. If you
own a hot air gun, you can make a home made hood out of sheet
metal. For temperature monitoring, you could use a
thermocouple connected to a multimeter.
http://en.wikipedia.org/wiki/Thermocouple
Paul
C
Charlie+
Guest
On Mon, 26 May 2014 05:51:12 +0000 (UTC), Calia <calia@its.invalid>
wrote as underneath :
You cant' reflow a motherboard and get away with it, you can sometimes
replace a single chip if you know exactly what your doing and exactly
which chip is the problem. Many laptops dont have plugin processors,
there is no chance of replacing a soldered-in one!
Suggest you head for the bin with this one having taken the hard drive
out and lifting off any files you need to keep.
If you really want to pursue the problem, there is a diagnostic board
you can get for not much money from China, which plugs into the parallel
port (which has direct access to the BOIS boot) and can watch every step
of any bootup, it remembers the 4 digit codes for every step in the
sequence so you can step through and interpret exactly where the BOIS
stops booting, cheap kit - but not for the faint hearted, check your
laptop has a parallel port!
See : eBay item number: 400514258135
C+
wrote as underneath :
You cant' reflow a motherboard and get away with it, you can sometimes
replace a single chip if you know exactly what your doing and exactly
which chip is the problem. Many laptops dont have plugin processors,
there is no chance of replacing a soldered-in one!
Suggest you head for the bin with this one having taken the hard drive
out and lifting off any files you need to keep.
If you really want to pursue the problem, there is a diagnostic board
you can get for not much money from China, which plugs into the parallel
port (which has direct access to the BOIS boot) and can watch every step
of any bootup, it remembers the 4 digit codes for every step in the
sequence so you can step through and interpret exactly where the BOIS
stops booting, cheap kit - but not for the faint hearted, check your
laptop has a parallel port!
See : eBay item number: 400514258135
C+
C
Calia
Guest
On Mon, 26 May 2014 04:48:06 +0100, Good Guy wrote:
Just because I could, I tried booting to Knoppix, but it didn't even
get to the BIOS screen, which, if the CPU is reporting itself bad,
would be the case.
I don't think Windows 7 would fare any better, but, I don't have a
Windows 7 boot disk anyway.
Just because I could, I tried booting to Knoppix, but it didn't even
get to the BIOS screen, which, if the CPU is reporting itself bad,
would be the case.
I don't think Windows 7 would fare any better, but, I don't have a
Windows 7 boot disk anyway.
W
Wond
Guest
On Mon, 26 May 2014 03:28:54 +0000, Calia wrote:
at the screen, and watch closely as you power up. Maybe just the backlight has
failed.
Before you have disassembled anything, shine a flashlight (electric torch)
at the screen, and watch closely as you power up. Maybe just the backlight has
failed.
K
Ken
Guest
Calia wrote:
You have received a lot of useful information and suggestions, so what I
am about to say may be for naught: I have two G72 laptops. One I
bought new and experienced much the same type of problem as you are
after the warranty ran out. Being that I am one who cannot accept a
device is not repairable, I dug into trouble shooting and repairing my
laptop. At first I opened it up and inspected the connections because
the problem was intermittent. I would disassemble the computer,
reassemble it, and it would work for a time. Then it would fail again.
Without going into great detail of all the steps, the solution to
fixing this computer was to re-solder the connections at the power
switch board. There appears to be an opto isolator on a daughter board
where the switch is mounted. It takes a steady hand and a low wattage
iron, but this computer has not failed in a couple of years since I
touched up the connections. I think I fixed it.
After having fixed the above computer, I purchased another G72 computer
on Ebay where the seller was encountering the same failure as mine. I
bought it for little, and thought I would use it for parts if my
computer ever failed. When I received it, it DID NOT include an AC
adapter. I plugged in my adapter to the computer and everything
worked!! That has been over a year now.
So what can one learn from the above? First off there appears to be
some experiencing such failures that are attributed to the power switch
board. There are such posts on the web. Second, if the adapter
delivers less than the proper level of voltage to the computer, it too
will fail in a similar manner. Measuring the voltage with a volt meter
is not going to work unless you load it down sufficiently. If it were
my computer, I would borrow a power adapter that you know works on that
model computer. If it does not solve the problem, suspect the power
switch board.
There are no guarantees as to what will solve your problem, and the fan
running seems to contradict my experience, but a lot is happening when
you start a computer. Any of them failing will negate the boot process.
Good luck.
You have received a lot of useful information and suggestions, so what I
am about to say may be for naught: I have two G72 laptops. One I
bought new and experienced much the same type of problem as you are
after the warranty ran out. Being that I am one who cannot accept a
device is not repairable, I dug into trouble shooting and repairing my
laptop. At first I opened it up and inspected the connections because
the problem was intermittent. I would disassemble the computer,
reassemble it, and it would work for a time. Then it would fail again.
Without going into great detail of all the steps, the solution to
fixing this computer was to re-solder the connections at the power
switch board. There appears to be an opto isolator on a daughter board
where the switch is mounted. It takes a steady hand and a low wattage
iron, but this computer has not failed in a couple of years since I
touched up the connections. I think I fixed it.
After having fixed the above computer, I purchased another G72 computer
on Ebay where the seller was encountering the same failure as mine. I
bought it for little, and thought I would use it for parts if my
computer ever failed. When I received it, it DID NOT include an AC
adapter. I plugged in my adapter to the computer and everything
worked!! That has been over a year now.
So what can one learn from the above? First off there appears to be
some experiencing such failures that are attributed to the power switch
board. There are such posts on the web. Second, if the adapter
delivers less than the proper level of voltage to the computer, it too
will fail in a similar manner. Measuring the voltage with a volt meter
is not going to work unless you load it down sufficiently. If it were
my computer, I would borrow a power adapter that you know works on that
model computer. If it does not solve the problem, suspect the power
switch board.
There are no guarantees as to what will solve your problem, and the fan
running seems to contradict my experience, but a lot is happening when
you start a computer. Any of them failing will negate the boot process.
Good luck.
C
Calia
Guest
On Mon, 26 May 2014 09:40:34 -0400, Wolf K wrote:
This is good advice, as had been all the prior advice.
I am heading down to Radio Shack today, if they're open, to pick
up an SATA/ATA USB adapter, which will make it very easy to get
all the data off the hard disk drive.
I've done that step before, and, even better, I recently
made a backup of my data hierarchy only about a month
ago, so there really isn't much data that I need to
back up incrementally anyway.
This is good advice, as had been all the prior advice.
I am heading down to Radio Shack today, if they're open, to pick
up an SATA/ATA USB adapter, which will make it very easy to get
all the data off the hard disk drive.
I've done that step before, and, even better, I recently
made a backup of my data hierarchy only about a month
ago, so there really isn't much data that I need to
back up incrementally anyway.
C
Calia
Guest
On Mon, 26 May 2014 14:44:02 +0000, Wond wrote:
I tried that, and saw nothing. Even in the dark.
I think the single blink of the numlock and capslock indicating a bad CPU
(or the power to it) is the issue.
Most people here seem to indicate that the CPU itself didn't fry, but,
that the solder joints honeycombed, and eventually cracked.
At least that's what I seem to have gotten so far out of the
conversation.
I tried that, and saw nothing. Even in the dark.
I think the single blink of the numlock and capslock indicating a bad CPU
(or the power to it) is the issue.
Most people here seem to indicate that the CPU itself didn't fry, but,
that the solder joints honeycombed, and eventually cracked.
At least that's what I seem to have gotten so far out of the
conversation.
W
Wolf K
Guest
On 2014-05-25 11:28 PM, Calia wrote:
I've read all the other advice, all of it good if you're comfortable
messing with hardware, etc.
However, your _first_ concern should be to get all your data off the
disk drive, and that can, and IMO should, be done without repairing the
machine. IMO best bet is to take the machine to a shop that can deal
with it. Then you can decide whether repair (by yourself or the shop) is
feasible.
HTH & Good Luck,
--
Best,
Wolf K
kirkwood40.blogspot.ca
I've read all the other advice, all of it good if you're comfortable
messing with hardware, etc.
However, your _first_ concern should be to get all your data off the
disk drive, and that can, and IMO should, be done without repairing the
machine. IMO best bet is to take the machine to a shop that can deal
with it. Then you can decide whether repair (by yourself or the shop) is
feasible.
HTH & Good Luck,
--
Best,
Wolf K
kirkwood40.blogspot.ca
P
pjp
Guest
In article <llvu8j$f1t$2@news.albasani.net>, calia@its.invalid says...
The manufacturer's site may have some info on what you "see" and "hear"
depending on what's wrong. Least used to be "x" beeps meant this and
"y" beeps meant that type idea, maybe lights do similar?
Internal power supply likely provides a number of leads with varying
power. Could be it's failed on one or more of them but not all hence see
leds lit on some keys?
Again an experienced shop would know how to test all that, I don't. I
also don't really like taking laptops apart IF I also have to put it
back together and have it run
I solder with a blowtorch LOL
The manufacturer's site may have some info on what you "see" and "hear"
depending on what's wrong. Least used to be "x" beeps meant this and
"y" beeps meant that type idea, maybe lights do similar?
Internal power supply likely provides a number of leads with varying
power. Could be it's failed on one or more of them but not all hence see
leds lit on some keys?
Again an experienced shop would know how to test all that, I don't. I
also don't really like taking laptops apart IF I also have to put it
back together and have it run
I solder with a blowtorch LOL
J
Jeff Liebermann
Guest
On Mon, 26 May 2014 17:37:55 +0000 (UTC), Calia <calia@its.invalid>
wrote:
That probably will work, especially since the drive is not failing and
there's little risk of losing anything on it.
In the future, you might consider doing an image backup instead. I
use Acronis True Image 2014, but there are free drive cloning programs
that will also work:
<http://clonezilla.org>
Some of the benefits of image backups are:
- Speed. I just did an SSD to USB 3.0 backup running at 6
GBytes/minute. Typcial for older machines and USB 2.0 is 1-2
GBytes/minute backup.
- It backups up literally everything. Nothing is missed. That's
great for programs the dump files in unusual places or strange stuff
in hidden partitions. Also works with UEFI boot.
- In this case, it will also get the recovery partition, which you
might need for a reinstall. The alternative is to order the recovery
DVD's from HP (about $30).
- etc...
I'm at the point that everything that is brought to the shop usually
gets backed up twice; once on arrival and once when it's done.
<http://802.11junk.com/jeffl/crud/backup-drives.jpg>
That's about 6TB of drives show. There is probably another 5TB of
drives that I've since the picture was taken. What makes this
practical is the speed of the backup (and restore).
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
wrote:
That probably will work, especially since the drive is not failing and
there's little risk of losing anything on it.
In the future, you might consider doing an image backup instead. I
use Acronis True Image 2014, but there are free drive cloning programs
that will also work:
<http://clonezilla.org>
Some of the benefits of image backups are:
- Speed. I just did an SSD to USB 3.0 backup running at 6
GBytes/minute. Typcial for older machines and USB 2.0 is 1-2
GBytes/minute backup.
- It backups up literally everything. Nothing is missed. That's
great for programs the dump files in unusual places or strange stuff
in hidden partitions. Also works with UEFI boot.
- In this case, it will also get the recovery partition, which you
might need for a reinstall. The alternative is to order the recovery
DVD's from HP (about $30).
- etc...
I'm at the point that everything that is brought to the shop usually
gets backed up twice; once on arrival and once when it's done.
<http://802.11junk.com/jeffl/crud/backup-drives.jpg>
That's about 6TB of drives show. There is probably another 5TB of
drives that I've since the picture was taken. What makes this
practical is the speed of the backup (and restore).
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
W
William Sommerwerck
Guest
"Calia" wrote in message news:llvu5j$f1t$1@news.albasani.net...
If you're near a computer-supply store, you might want to look for Vantec. I
can recommend them from personal experience.
www.vantecusa.com
If you're near a computer-supply store, you might want to look for Vantec. I
can recommend them from personal experience.
www.vantecusa.com
C
Calia
Guest
On Tue, 27 May 2014 00:00:05 +0100, J. P. Gilliver (John) wrote:
> melting the solder on the pins of the IC with a hot air blower.
I was wondering what that was, as he seemed too close for it
to be a flame burner.
> melting the solder on the pins of the IC with a hot air blower.
I was wondering what that was, as he seemed too close for it
to be a flame burner.
C
Calia
Guest
On Tue, 27 May 2014 00:00:05 +0100, J. P. Gilliver (John) wrote:
I had never heard of this "kapton" tape!
Googling, I'm still not sure what it is, but it must be a great
insulator.
http://en.wikipedia.org/wiki/Kapton
I had never heard of this "kapton" tape!
Googling, I'm still not sure what it is, but it must be a great
insulator.
http://en.wikipedia.org/wiki/Kapton
C
Calia
Guest
On Tue, 27 May 2014 00:00:05 +0100, J. P. Gilliver (John) wrote:
I hadn't even thought of that!
It's a great idea.
I have one at work, which I can test out tomorrow!
Thanks!
I hadn't even thought of that!
It's a great idea.
I have one at work, which I can test out tomorrow!
Thanks!
J
J. P. Gilliver (John)
Guest
In message <llukog$jrf$5@news.albasani.net>, Calia <calia@its.invalid>
writes:
Step by step through that video:
melting the solder on the pins of the IC with a hot air blower.
Personally, I'd have some Kapton tape (like the yellow tape visible near
the top of the video around just after 7 minutes in) over the other
small components around: not so much as to keep them in place - if
they're decoupling capacitors, it _might_ not matter too much if they're
lost - as to stop them going off and shorting something else. It's easy
not to detect these almost microscopic components.
Removing the IC. I'm pretty certain there was a skip in the video, as it
seems to disappear by magic - one moment it's there, the next it isn't.
The most important thing is to make sure all the solder is really
melted: if it isn't at just one or two pins, you can pull off tracks
(which are the devil to repair) when you pull the IC off. Ideally it
will just blow away.
Cleaning up the solder pads. That's what he's doing with the solder
braid (the copper woven strip) and soldering iron. Basically, you want
to clean the pads until they're flat, no solder (other than a very thin
flat layer).
Applying solder and replacement chip. It looks like he applied solder
and then reheated it all with the hot air again. I'm sure that can be
made to work; the way I usually do it is manually tack two opposing legs
to hold the chip in place, then go around chasing a blob of solder
around the remaining legs: amazingly, this does work, if the
solder-resist is in reasonably condition. Lining the chip up before
tacking is the difficult bit - doable, just takes patience (and a second
or third try if it moves during the tacking: you just have to groan and
do it, don't go ahead and assume you can fix it after you've soldered
_all_ the legs).
The second half of the video seems to be replacing a surface-mount
connector, by much the same means, though I think he does use tacking
this time.
I'd agree with those expressing doubt as to whether it's worth it, and
try with an external monitor first.
(Also, my own - extremely limited! - experience of laptop repair has
been that cracks - in the solder joints or the PCB tracks around them -
in the vicinity of the power input connector can be the problem: and
lights can still come on, just there isn't enough power getting through
to do anything else. If it gets to a dismantling and possible soldering
activity, I'd reflow the solder around those before anything else: a lot
easier than the finer chips. My experience replacing chips is genuine
[avionics], but not with laptops. And I wouldn't expect to be able to
reflow a ball-grid array.)
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
he was eventually struck off by the BMA in 1968 for not knowing his gluteus
maximus from his humerus.
writes:
Step by step through that video:
melting the solder on the pins of the IC with a hot air blower.
Personally, I'd have some Kapton tape (like the yellow tape visible near
the top of the video around just after 7 minutes in) over the other
small components around: not so much as to keep them in place - if
they're decoupling capacitors, it _might_ not matter too much if they're
lost - as to stop them going off and shorting something else. It's easy
not to detect these almost microscopic components.
Removing the IC. I'm pretty certain there was a skip in the video, as it
seems to disappear by magic - one moment it's there, the next it isn't.
The most important thing is to make sure all the solder is really
melted: if it isn't at just one or two pins, you can pull off tracks
(which are the devil to repair) when you pull the IC off. Ideally it
will just blow away.
Cleaning up the solder pads. That's what he's doing with the solder
braid (the copper woven strip) and soldering iron. Basically, you want
to clean the pads until they're flat, no solder (other than a very thin
flat layer).
Applying solder and replacement chip. It looks like he applied solder
and then reheated it all with the hot air again. I'm sure that can be
made to work; the way I usually do it is manually tack two opposing legs
to hold the chip in place, then go around chasing a blob of solder
around the remaining legs: amazingly, this does work, if the
solder-resist is in reasonably condition. Lining the chip up before
tacking is the difficult bit - doable, just takes patience (and a second
or third try if it moves during the tacking: you just have to groan and
do it, don't go ahead and assume you can fix it after you've soldered
_all_ the legs).
The second half of the video seems to be replacing a surface-mount
connector, by much the same means, though I think he does use tacking
this time.
I'd agree with those expressing doubt as to whether it's worth it, and
try with an external monitor first.
(Also, my own - extremely limited! - experience of laptop repair has
been that cracks - in the solder joints or the PCB tracks around them -
in the vicinity of the power input connector can be the problem: and
lights can still come on, just there isn't enough power getting through
to do anything else. If it gets to a dismantling and possible soldering
activity, I'd reflow the solder around those before anything else: a lot
easier than the finer chips. My experience replacing chips is genuine
[avionics], but not with laptops. And I wouldn't expect to be able to
reflow a ball-grid array.)
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
he was eventually struck off by the BMA in 1968 for not knowing his gluteus
maximus from his humerus.
J
Jeff Liebermann
Guest
On Mon, 26 May 2014 11:49:48 -0700, "William Sommerwerck"
<grizzledgeezer@comcast.net> wrote:
This model?
<http://www.vantecusa.com/en/product/view_detail/586>
$27 from NewEgg.
<http://www.newegg.com/Product/Product.aspx?Item=N82E16812232033>
Ouch. Note that I'm buying USB 3.0 these days because it's becoming
common and the speed improvement is worthwhile.
Cheaper on eBay:
<http://www.ebay.com/sch/i.html?_sacat=0&_from=R40&LH_BIN=1&_nkw=usb+3.0+SATA+adapter&rt=nc&LH_PrefLoc=3>
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
<grizzledgeezer@comcast.net> wrote:
This model?
<http://www.vantecusa.com/en/product/view_detail/586>
$27 from NewEgg.
<http://www.newegg.com/Product/Product.aspx?Item=N82E16812232033>
Ouch. Note that I'm buying USB 3.0 these days because it's becoming
common and the speed improvement is worthwhile.
Cheaper on eBay:
<http://www.ebay.com/sch/i.html?_sacat=0&_from=R40&LH_BIN=1&_nkw=usb+3.0+SATA+adapter&rt=nc&LH_PrefLoc=3>
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
W
William Sommerwerck
Guest
"Calia" wrote in message news:lm0tri$g4v$2@news.albasani.net...
> I had never heard of this "kapton" tape!
My heavens! Stephen Foster wrote a song about it in the 19th century -- "De
Kapton Races"!
"Oh, de Kapton ladies sing dis song --
Doo-dah, doo-dah.
De Kapton racetrack five miles long --
Oh, de doo-dah day."
Kapton has been used to make orthodynamic loudspeakers. It's also used to
cover waveguide ports, so the nitrogen within won't get without. (The
waveguides are filled with dry nitrogen to keep moisture out.)
> I had never heard of this "kapton" tape!
My heavens! Stephen Foster wrote a song about it in the 19th century -- "De
Kapton Races"!
"Oh, de Kapton ladies sing dis song --
Doo-dah, doo-dah.
De Kapton racetrack five miles long --
Oh, de doo-dah day."
Kapton has been used to make orthodynamic loudspeakers. It's also used to
cover waveguide ports, so the nitrogen within won't get without. (The
waveguides are filled with dry nitrogen to keep moisture out.)