Toshiba Laptop

[jinxy]

Hello, I have recently been given an older Toshiba laptop, TecraS2.
This system runs Xp pro,1.5gigs of ram(pc2700) and is a Mobile Intel
Pentium M-750 @1.86ghz. The catch is the thing wont run. The power
comes on and I can hear the harddrive running and the cpu fan spins,
but no display and no sound. I have tried to boot from a Windows XP
disk, but no joy. I have tried to hook it up to an external monitor
and still no screen. The HD has been swapped out , no luck with that.
Got any ideas as to why this LT wont boot up , I would like to hear
them.
thanks in advance for you help and support.
..-J

 

[Paul]

Hello, I have recently been given an older Toshiba laptop, TecraS2.
This system runs Xp pro,1.5gigs of ram(pc2700) and is a Mobile Intel
Pentium M-750 @1.86ghz. The catch is the thing wont run. The power
comes on and I can hear the harddrive running and the cpu fan spins,
but no display and no sound. I have tried to boot from a Windows XP
disk, but no joy. I have tried to hook it up to an external monitor
and still no screen. The HD has been swapped out , no luck with that.
Got any ideas as to why this LT wont boot up , I would like to hear
them.
thanks in advance for you help and support.
.-J

On a desktop, you'd get beeping if the processor was alive,
but the RAM was missing. I don't know if a laptop shares that
feature or not. You could try unplugging the RAM, and see
if it complains. That isn't going to work though, if the
laptop has some minimum amount of RAM soldered right to the
motherboard itself. It would only work (generate beep code),
if all RAM can be unplugged.

One possible explanation, is a failure in the Vcore circuit,
to provide power to the processor. Something has to convert
the 14.4V from the battery, into 1.5V or less for the processor.
That's a switching converter. Other switching converter circuits,
provide 5V to run the laptop hard drive, 5V to run USB ports,
3.3V and some lower voltages, to run the chipset.

Another possibility, is a dead CMOS battery. In a laptop, that
could be a two wire twisted cable, with a CR2032 inside a shrink
wrap tube for insulation. On some desktops at least,
a dead CMOS battery has been known to prevent booting. On
my desktops here, where the battery ran flat, I was still
able to start them. So not all computers are affected in
that way. But occasionally, I find reports of computers
that started properly, once the CR2032 was exchanged for
a fresh one. You'll need to open the unit, and it might
require removing more than just the RAM door,
to find that CMOS battery. Using your multimeter, you'd check
the voltage on the battery. Less than 2.4V would likely mean it
is time to change it.

(Photo showing one way to package a CMOS battery for a laptop...)

http://www.christopherlowe.name/wp-...6026-TP600E-CMOS-battery-replacement 0011.jpg

Paul

 

[jinxy]

On a desktop, you'd get beeping if the processor was alive,
but the RAM was missing. I don't know if a laptop shares that
feature or not. You could try unplugging the RAM, and see
if it complains. That isn't going to work though, if the
laptop has some minimum amount of RAM soldered right to the
motherboard itself. It would only work (generate beep code),
if all RAM can be unplugged.

One possible explanation, is a failure in the Vcore circuit,
to provide power to the processor. Something has to convert
the 14.4V from the battery, into 1.5V or less for the processor.
That's a switching converter. Other switching converter circuits,
provide 5V to run the laptop hard drive, 5V to run USB ports,
3.3V and some lower voltages, to run the chipset.

Another possibility, is a dead CMOS battery. In a laptop, that
could be a two wire twisted cable, with a CR2032 inside a shrink
wrap tube for insulation. On some desktops at least,
a dead CMOS battery has been known to prevent booting. On
my desktops here, where the battery ran flat, I was still
able to start them. So not all computers are affected in
that way. But occasionally, I find reports of computers
that started properly, once the CR2032 was exchanged for
a fresh one. You'll need to open the unit, and it might
require removing more than just the RAM door,
to find that CMOS battery. Using your multimeter, you'd check
the voltage on the battery. Less than 2.4V would likely mean it
is time to change it.

(Photo showing one way to package a CMOS battery for a laptop...)

http://www.christopherlowe.name/wp-content/uploads/2006/02/2006026-TP...

    Paul

I will try that in the morning and post back any results. Thanks again
-J

 

[jinxy]

I will try that in the morning and post back any results. Thanks again
-J- Hide quoted text -

- Show quoted text -

Couldn't wait til morning. I took the unit apart. The battery was
soldered to the underside of the motherboard, close to the cpu fan and
heatsink. When tested, it showed an output of 3v. I don't think that
the battery is the culprit. I am open to any other suggestions. I
would like to bring this thing back to life, even if just as a
learning tool.
-J