motherboard cpu power section check

M

Mike De Petris

Guest
My laptop freezes when I connect the power cord, works well on battery
only.

I want to check the motherbard in search for the faulty component,
where could I find pinouts and voltages to check for?

Toshiba Satellite A205-S4577 (PSAF0U-01Q009)

Laptop Motherboard: MAIN BOARD 945GM. Main Board 945GM EXC+51 CA+MIC
MDC 1310A2120812 Alternate Part Numbers: V000108030

Processor:
LF80537 T5300
5648B999 SL9WE
1.73/2M/533
INTEL... copyright 06
 
Mike De Petris wrote:
My laptop freezes when I connect the power cord, works well on battery
only.

I want to check the motherbard in search for the faulty component,
where could I find pinouts and voltages to check for?

Toshiba Satellite A205-S4577 (PSAF0U-01Q009)

Laptop Motherboard: MAIN BOARD 945GM. Main Board 945GM EXC+51 CA+MIC
MDC 1310A2120812 Alternate Part Numbers: V000108030

Processor:
LF80537 T5300
5648B999 SL9WE
1.73/2M/533
INTEL... copyright 06
Click to expand...
I don't know about acquiring a schematic for trouble shooting the MB,
but the first thing I would do is test the power adapter with a load
attached. I have repaired several that output the correct voltage but
failed to regulate when loaded down.

Also, some Toshiba Satellite computers were notorious for having power
connector problems. I trust this computer does NOT have such a problem?
 
On Aug 13, 1:43 pm, Ken <K...@invalid.com> wrote:
Mike De Petris wrote:
My laptop freezes when I connect the power cord, works well on battery
only.

I want to check the motherbard in search for the faulty component,
where could I find pinouts and voltages to check for?

Toshiba Satellite A205-S4577 (PSAF0U-01Q009)

Laptop Motherboard: MAIN BOARD 945GM. Main Board 945GM EXC+51 CA+MIC
MDC 1310A2120812 Alternate Part Numbers: V000108030

Processor:
LF80537    T5300
5648B999  SL9WE
1.73/2M/533
INTEL... copyright 06

        I don't know about acquiring a schematic for trouble shooting the MB,
but the first thing I would do is test the power adapter with a load
attached.  I have repaired several that output the correct voltage but
failed to regulate when loaded down.

        Also, some Toshiba Satellite computers were notorious for having power
connector problems.  I trust this computer does NOT have such a problem?
Click to expand...
no problems on the connector
tried different power supplies, even stabilized laboratory psu
 
On Fri, 13 Aug 2010 04:55:24 -0700, Mike De Petris wrote:

On Aug 13, 1:43 pm, Ken <K...@invalid.com> wrote:
Mike De Petris wrote:
My laptop freezes when I connect the power cord, works well on
battery only.

I want to check the motherbard in search for the faulty component,
where could I find pinouts and voltages to check for?

Toshiba Satellite A205-S4577 (PSAF0U-01Q009)

Laptop Motherboard: MAIN BOARD 945GM. Main Board 945GM EXC+51 CA+MIC
MDC 1310A2120812 Alternate Part Numbers: V000108030

Processor:
LF80537    T5300
5648B999  SL9WE
1.73/2M/533
INTEL... copyright 06

        I don't know about acquiring a schematic for trouble
        shooting the MB,
but the first thing I would do is test the power adapter with a load
attached.  I have repaired several that output the correct voltage but
failed to regulate when loaded down.

        Also, some Toshiba Satellite computers were notorious for
        having power
connector problems.  I trust this computer does NOT have such a
problem?

no problems on the connector
tried different power supplies, even stabilized laboratory psu
Click to expand...
Did you try cleaning the air ducts? When on batter the CPU 'may' be at a
reduced clock speed via Toshiba Power Management when on battery. When on
the PSU, the CPU will go to full speed and may just be over heating.

Food for thought --




--
Live Fast, Die Young and Leave a Pretty Corpse
 
On Aug 13, 4:23 pm, Meat Plow <mhyw...@yahoo.com> wrote:
On Fri, 13 Aug 2010 04:55:24 -0700, Mike De Petris wrote:
On Aug 13, 1:43 pm, Ken <K...@invalid.com> wrote:
Mike De Petris wrote:
My laptop freezes when I connect the power cord, works well on
battery only.

I want to check the motherbard in search for the faulty component,
where could I find pinouts and voltages to check for?

Toshiba Satellite A205-S4577 (PSAF0U-01Q009)

Laptop Motherboard: MAIN BOARD 945GM. Main Board 945GM EXC+51 CA+MIC
MDC 1310A2120812 Alternate Part Numbers: V000108030

Processor:
LF80537    T5300
5648B999  SL9WE
1.73/2M/533
INTEL... copyright 06

        I don't know about acquiring a schematic for trouble
        shooting the MB,
but the first thing I would do is test the power adapter with a load
attached.  I have repaired several that output the correct voltage but
failed to regulate when loaded down.

        Also, some Toshiba Satellite computers were notorious for
        having power
connector problems.  I trust this computer does NOT have such a
problem?

no problems on the connector
tried different power supplies, even stabilized laboratory psu

Did you try cleaning the air ducts? When on batter the CPU 'may' be at a
reduced clock speed via Toshiba Power Management when on battery. When on
the PSU, the CPU will go to full speed and may just be over heating.

Food for thought --
Click to expand...
thank you, anyway please consider the laptop is completely teared a
part, non problems of air flow, and when connectinh power it locks
immediately even if in the BIOS pages
 
On Fri, 13 Aug 2010 09:25:13 -0700, Mike De Petris wrote:

On Aug 13, 4:23 pm, Meat Plow <mhyw...@yahoo.com> wrote:
On Fri, 13 Aug 2010 04:55:24 -0700, Mike De Petris wrote:
On Aug 13, 1:43 pm, Ken <K...@invalid.com> wrote:
Mike De Petris wrote:
My laptop freezes when I connect the power cord, works well on
battery only.

I want to check the motherbard in search for the faulty component,
where could I find pinouts and voltages to check for?

Toshiba Satellite A205-S4577 (PSAF0U-01Q009)

Laptop Motherboard: MAIN BOARD 945GM. Main Board 945GM EXC+51
CA+MIC MDC 1310A2120812 Alternate Part Numbers: V000108030

Processor:
LF80537    T5300
5648B999  SL9WE
1.73/2M/533
INTEL... copyright 06

        I don't know about acquiring a schematic for trouble
        shooting the MB,
but the first thing I would do is test the power adapter with a load
attached.  I have repaired several that output the correct voltage
but failed to regulate when loaded down.

        Also, some Toshiba Satellite computers were notorious
        for having power
connector problems.  I trust this computer does NOT have such a
problem?

no problems on the connector
tried different power supplies, even stabilized laboratory psu

Did you try cleaning the air ducts? When on batter the CPU 'may' be at
a reduced clock speed via Toshiba Power Management when on battery.
When on the PSU, the CPU will go to full speed and may just be over
heating.

Food for thought --

thank you, anyway please consider the laptop is completely teared a
part, non problems of air flow, and when connectinh power it locks
immediately even if in the BIOS pages
Click to expand...
Had no way of knowing since you didn't mention these additional facts in
your original post.



--
Live Fast, Die Young and Leave a Pretty Corpse
 
On Aug 13, 6:41 pm, Meat Plow <mhyw...@yahoo.com> wrote:
On Fri, 13 Aug 2010 09:25:13 -0700, Mike De Petris wrote:
On Aug 13, 4:23 pm, Meat Plow <mhyw...@yahoo.com> wrote:
On Fri, 13 Aug 2010 04:55:24 -0700, Mike De Petris wrote:
On Aug 13, 1:43 pm, Ken <K...@invalid.com> wrote:
Mike De Petris wrote:
My laptop freezes when I connect the power cord, works well on
battery only.

I want to check the motherbard in search for the faulty component,
where could I find pinouts and voltages to check for?

Toshiba Satellite A205-S4577 (PSAF0U-01Q009)

Laptop Motherboard: MAIN BOARD 945GM. Main Board 945GM EXC+51
CA+MIC MDC 1310A2120812 Alternate Part Numbers: V000108030

Processor:
LF80537    T5300
5648B999  SL9WE
1.73/2M/533
INTEL... copyright 06

        I don't know about acquiring a schematic for trouble
        shooting the MB,
but the first thing I would do is test the power adapter with a load
attached.  I have repaired several that output the correct voltage
but failed to regulate when loaded down.

        Also, some Toshiba Satellite computers were notorious
        for having power
connector problems.  I trust this computer does NOT have such a
problem?

no problems on the connector
tried different power supplies, even stabilized laboratory psu

Did you try cleaning the air ducts? When on batter the CPU 'may' be at
a reduced clock speed via Toshiba Power Management when on battery.
When on the PSU, the CPU will go to full speed and may just be over
heating.

Food for thought --

thank you, anyway please consider the laptop is completely teared a
part, non problems of air flow, and when connectinh power it locks
immediately even if in the BIOS pages

Had no way of knowing since you didn't mention these additional facts in
your original post.
Click to expand...
I'm sorry, I'm just forgetting pieces as I wrote this long story many
time in different newsgroups and forums, and still need to find a
solution.

Anyway I can still use the laptop on battery, or giving 12V with an
ATX PSU in place of the positive battery pole, leaving other battery
contacts in place.
 
Mike De Petris wrote:
On Aug 13, 6:41 pm, Meat Plow<mhyw...@yahoo.com> wrote:
On Fri, 13 Aug 2010 09:25:13 -0700, Mike De Petris wrote:
On Aug 13, 4:23 pm, Meat Plow<mhyw...@yahoo.com> wrote:
On Fri, 13 Aug 2010 04:55:24 -0700, Mike De Petris wrote:
On Aug 13, 1:43 pm, Ken<K...@invalid.com> wrote:
Mike De Petris wrote:
My laptop freezes when I connect the power cord, works well on
battery only.

I want to check the motherbard in search for the faulty component,
where could I find pinouts and voltages to check for?

Toshiba Satellite A205-S4577 (PSAF0U-01Q009)

Laptop Motherboard: MAIN BOARD 945GM. Main Board 945GM EXC+51
CA+MIC MDC 1310A2120812 Alternate Part Numbers: V000108030

Processor:
LF80537 T5300
5648B999 SL9WE
1.73/2M/533
INTEL... copyright 06

I don't know about acquiring a schematic for trouble
shooting the MB,
but the first thing I would do is test the power adapter with a load
attached. I have repaired several that output the correct voltage
but failed to regulate when loaded down.

Also, some Toshiba Satellite computers were notorious
for having power
connector problems. I trust this computer does NOT have such a
problem?

no problems on the connector
tried different power supplies, even stabilized laboratory psu

Did you try cleaning the air ducts? When on batter the CPU 'may' be at
a reduced clock speed via Toshiba Power Management when on battery.
When on the PSU, the CPU will go to full speed and may just be over
heating.

Food for thought --

thank you, anyway please consider the laptop is completely teared a
part, non problems of air flow, and when connectinh power it locks
immediately even if in the BIOS pages

Had no way of knowing since you didn't mention these additional facts in
your original post.

I'm sorry, I'm just forgetting pieces as I wrote this long story many
time in different newsgroups and forums, and still need to find a
solution.

Anyway I can still use the laptop on battery, or giving 12V with an
ATX PSU in place of the positive battery pole, leaving other battery
contacts in place.
Click to expand...
Have you looked at the MB power bus (+5v I would assume) for ripple
when you attach the external power supply?
 
On Fri, 13 Aug 2010 10:14:22 -0700, Mike De Petris wrote:

On Aug 13, 6:41 pm, Meat Plow <mhyw...@yahoo.com> wrote:
On Fri, 13 Aug 2010 09:25:13 -0700, Mike De Petris wrote:
On Aug 13, 4:23 pm, Meat Plow <mhyw...@yahoo.com> wrote:
On Fri, 13 Aug 2010 04:55:24 -0700, Mike De Petris wrote:
On Aug 13, 1:43 pm, Ken <K...@invalid.com> wrote:
Mike De Petris wrote:
My laptop freezes when I connect the power cord, works well on
battery only.

I want to check the motherbard in search for the faulty
component, where could I find pinouts and voltages to check
for?

Toshiba Satellite A205-S4577 (PSAF0U-01Q009)

Laptop Motherboard: MAIN BOARD 945GM. Main Board 945GM EXC+51
CA+MIC MDC 1310A2120812 Alternate Part Numbers: V000108030

Processor:
LF80537    T5300
5648B999  SL9WE
1.73/2M/533
INTEL... copyright 06

        I don't know about acquiring a schematic for trouble
        shooting the MB,
but the first thing I would do is test the power adapter with a
load attached.  I have repaired several that output the correct
voltage but failed to regulate when loaded down.

        Also, some Toshiba Satellite computers were notorious
        for having power
connector problems.  I trust this computer does NOT have such a
problem?

no problems on the connector
tried different power supplies, even stabilized laboratory psu

Did you try cleaning the air ducts? When on batter the CPU 'may' be
at a reduced clock speed via Toshiba Power Management when on
battery. When on the PSU, the CPU will go to full speed and may just
be over heating.

Food for thought --

thank you, anyway please consider the laptop is completely teared a
part, non problems of air flow, and when connectinh power it locks
immediately even if in the BIOS pages

Had no way of knowing since you didn't mention these additional facts
in your original post.

I'm sorry, I'm just forgetting pieces as I wrote this long story many
time in different newsgroups and forums, and still need to find a
solution.

Anyway I can still use the laptop on battery, or giving 12V with an ATX
PSU in place of the positive battery pole, leaving other battery
contacts in place.
Click to expand...
Usually those things run off a 19 volt 95 watt PSU.



--
Live Fast, Die Young and Leave a Pretty Corpse
 
Mike De Petris wrote:
On Aug 13, 9:54 pm, Ken<K...@invalid.com> wrote:
Have you looked at the MB power bus (+5v I would assume) for ripple
when you attach the external power supply?

this is what I am asking for, I tought I should measure it at the
socket pin holes, how can I idetify the +5V line on the motherboard?

My guess is the hard drive is operating on +5v. You could measure it
Click to expand...
there.

And how would you measure (and fix the cause) a ripple on the bus? I
have a couple of scopes and multimeters for that, but how?
Click to expand...
First determine if it has ripple. You can normally take a volt meter
set for AC and measure the ripple on a DC bus. Old VOM's used a cap to
isolate the AC from the DC component, but the new DVM's generally work
for this. If you did find ripple, look for a cap that is bad or
possibly a diode that is shorted. First determine if it exists.
 
On Aug 13, 9:54 pm, Ken <K...@invalid.com> wrote:
        Have you looked at the MB power bus (+5v I would assume) for ripple
when you attach the external power supply?
Click to expand...
this is what I am asking for, I tought I should measure it at the
socket pin holes, how can I idetify the +5V line on the motherboard?

And how would you measure (and fix the cause) a ripple on the bus? I
have a couple of scopes and multimeters for that, but how?
 
On Aug 13, 9:13 pm, Meat Plow <mhyw...@yahoo.com> wrote:
Anyway I can still use the laptop on battery, or giving 12V with an ATX
PSU in place of the positive battery pole, leaving other battery
contacts in place.

Usually those things run off a 19 volt 95 watt PSU.
Click to expand...
yes of course, but this motherboard does not like it any more, 12V
from the battery (or external, faking the battery connector) is still
ok instead
 
On Aug 13, 9:25 am, Mike De Petris <mikedepet...@gmail.com> wrote:

... the laptop is completely teared a
part, non problems of air flow, and when connectinh power it locks
immediately even if in the BIOS pages
Click to expand...
There's a second CPU (a little tiny one) that handles the power
sequencing. The 'BIOS pages' are only for the big CPU, it's that
little battery-monitor one that runs into some kind of trouble, and
it has that problem every time the external power is applied and
it tries to do the natural thing, run the computer from external
power and charge the battery. Somehow it senses overvoltage
or overcurrent and shuts down.

Look for small-value current sense resistors that are open, or
for semiconductor switches that are shorted (can't turn off).
There are often PMOS power switch transistors involved.
Also, look for fuses (they might not LOOK like fuses, though).

Battery charge current might be channeled through a switchmode
regulator, those have always had problems if a capacitor fails.
 
A schematic of the Toshiba A205 series can be found in this forum:

www.reepair.net/en

Here's a really good website about Toshiba laptops:

www.IrisVista.com
 
"Mike De Petris" <mikedepetris@gmail.com> wrote in message
news:b76de8d0-9d51-41df-829f-0599838d7c0c@i31g2000yqm.googlegroups.com...
My laptop freezes when I connect the power cord, works well on battery
only.

I want to check the motherbard in search for the faulty component,
where could I find pinouts and voltages to check for?

Toshiba Satellite A205-S4577 (PSAF0U-01Q009)

Laptop Motherboard: MAIN BOARD 945GM. Main Board 945GM EXC+51 CA+MIC
MDC 1310A2120812 Alternate Part Numbers: V000108030

Processor:
LF80537 T5300
5648B999 SL9WE
1.73/2M/533
INTEL... copyright 06
Click to expand...
try here

http://www.reepair.net/en/forumdisplay.php/30-Laptop-Schematics

zack
 
On Aug 14, 2:47 am, "larry moe 'n curly" <larrymoencu...@my-deja.com>
wrote:
A schematic of the Toshiba A205 series can be found in this forum:

   www.reepair.net/en

Here's a really good website about Toshiba laptops:

   www.IrisVista.com
Click to expand...
great !! thank you, will have a deep reading
 
On Fri, 13 Aug 2010 01:56:24 -0700 (PDT), Mike De Petris
<mikedepetris@gmail.com> wrote:

My laptop freezes when I connect the power cord, works well on battery
only.
Toshiba Satellite A205-S4577 (PSAF0U-01Q009)
Click to expand...
<http://laptopforums.toshiba.com/t5/Batteries-and-Power/Laptop-will-only-run-on-battery-freezes-when-the-ac-is-plugged/m-p/114865>
(5 pages). Lots of good suggestions some of which include successful
repairs.
More:
<http://www.fixya.com/support/t2946491-freeze_when_power_cord_plugged_in>
<http://laptopforums.toshiba.com/t5/Batteries-and-Power/Laptop-shuts-down-as-soon-as-adapter-plugged-in/td-p/114041>

I've seen this twice and fixed it more by accident than by intent. In
one case, I left the battery out of the laptop, and no charger plugged
in, for about a weekend. When I returned on Monday, everything
magically worked normally. In the 2nd case, I was trying various
combinations of starting the computer, with the battery, without the
battery, with both, etc. At one point, it magically started working.
That was about 1-2 years ago, and both customers are still using the
laptops.

However, I have another Toshiblah laptop in the office with similar
(not identical) problems, that I can't fix. It also won't charge the
battery, although it will run on battery if I charge it in another
laptop. The problem was traced to a crappy BGA soldering job on the
video chip. Try booting from battery in Safe Mode, and then plug in
the charger. If that works, then it's probable that you have a video
chip soldering problem. (I'm debating the merits of buying an
overpriced hot air rework station. I borrowed one, liked it, but had
to return it).

Please do not tinker with external power supplies unless you're
absolutely sure you're using the correct power plug, and the correct
voltage. I've seen what's left of the laptop when the clip leads get
swapped, or the power supply mysteriously got to maximum. It's not
pretty. The correct power supply is 19v 3.4A negative ground,
5.5/2.5/12mm connector.

--
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
 
On Aug 15, 6:03 am, Jeff Liebermann <je...@cruzio.com> wrote:
My laptop freezes when I connect the power cord, works well on battery
only.
Toshiba Satellite A205-S4577 (PSAF0U-01Q009)
Click to expand...
thanks to your suggestions, I did a BIG step forward, I had a try at
this:
"In SafeMode Goto control panel--> device manager---> goto
processor----> disable one of the two processors --> reboot normally.
This FIXED the problem, but 1processor is not really a great fix; more
of a work around."

And IT WORKS, pc is now running on external power at the moment, a
thing that I've never seen on it. I tryed disabling a cpu core in BIOS
in the past unsuccesfully, but disableng from devmgmt.msc fixed it.

I do not think it can be a ripple problem because it did not boot at
all when connected on power, but who know? Still have to understand if
it is:
- faulty cpu
- faulty cpu power section
- bad cpu/other microcode

I would try to see with scope and multimeter but still don't know
exactly what and where to look for.
 
On Sun, 15 Aug 2010 15:13:09 +0000 (UTC), Meat Plow
<mhywatt@yahoo.com> wrote:

Is that a dual core CPU or hyperthreaded single core.
Click to expand...
1.73GHz Intel Core 2 Duo Mobile T5300


--
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
 
On Sun, 15 Aug 2010 02:12:28 -0700, Mike De Petris wrote:

On Aug 15, 6:03 am, Jeff Liebermann <je...@cruzio.com> wrote:
My laptop freezes when I connect the power cord, works well on battery
only.
Toshiba Satellite A205-S4577 (PSAF0U-01Q009)

thanks to your suggestions, I did a BIG step forward, I had a try at
this:
"In SafeMode Goto control panel--> device manager---> goto
processor----> disable one of the two processors --> reboot normally.
This FIXED the problem, but 1processor is not really a great fix; more
of a work around."

And IT WORKS, pc is now running on external power at the moment, a thing
that I've never seen on it. I tryed disabling a cpu core in BIOS in the
past unsuccesfully, but disableng from devmgmt.msc fixed it.

I do not think it can be a ripple problem because it did not boot at all
when connected on power, but who know? Still have to understand if it
is:
- faulty cpu
- faulty cpu power section
- bad cpu/other microcode

I would try to see with scope and multimeter but still don't know
exactly what and where to look for.
Click to expand...

Is that a dual core CPU or hyperthreaded single core.


--
Live Fast, Die Young and Leave a Pretty Corpse
 
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