ibm thinkpad T41 video problem


M

Mark O. Schlegel

I have a thinkpad T41, 2379-DJU, just recently it has a problem where
the instant it comes on the LCD just shows a jumbled mix of pixels.
There is actually a repeated pattern to the pixels so I
think the underlying software is working but the video
hardware has a problem.

Since I can see the pixels move in a consistent way, I can
tell the OS (Fedora Core 4) is properly booting and coming
to the login prompt. Linux has virtual consoles that are
reachable by pressing Alt+F# where # is a number from 1 to 7.

By blindly putting in the username/password, I can actually login and
start X windows. I know X windows started because of the color and
pattern changes in the mix of pixels. I can also see a blob moving
around in time with the mouse so again I'm sure Xwindows is working.

I also know that linux is not the problem because the LCD is screwed up
the instant the laptop powers up, I can't even see the notice to press
the bios setup button that usually would show.

So my guess is the video hardware itself is shot or the LCD driver that
drives the LCD. Unfortunately I can't access the thinkpad via
a network connection to work at diagnosing it because I didn't get to
the point in my installation of Fedora of activating ssh (secure shell).

I believe the T41 has the video right on the motherboard so
is the only way to fix that to replace the whole mainboard?
Any other ideas?

BTW, this same laptop was doing similar things a few months
back when booted cold but if I rebooted it one more time or so it would
come up ok -- kind of like some circuitry had to warm up to
work ok. It looks like something recently pushed it over the edge
and maybe the video ram went bad.

Mark
 
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F

fredman

I have a thinkpad T41, 2379-DJU, just recently it has a problem where
the instant it comes on the LCD just shows a jumbled mix of pixels.
There is actually a repeated pattern to the pixels so I
think the underlying software is working but the video
hardware has a problem.

Since I can see the pixels move in a consistent way, I can
tell the OS (Fedora Core 4) is properly booting and coming
to the login prompt. Linux has virtual consoles that are
reachable by pressing Alt+F# where # is a number from 1 to 7.

By blindly putting in the username/password, I can actually login and
start X windows. I know X windows started because of the color and
pattern changes in the mix of pixels. I can also see a blob moving
around in time with the mouse so again I'm sure Xwindows is working.

I also know that linux is not the problem because the LCD is screwed up
the instant the laptop powers up, I can't even see the notice to press
the bios setup button that usually would show.

So my guess is the video hardware itself is shot or the LCD driver that
drives the LCD. Unfortunately I can't access the thinkpad via
a network connection to work at diagnosing it because I didn't get to
the point in my installation of Fedora of activating ssh (secure shell).

I believe the T41 has the video right on the motherboard so
is the only way to fix that to replace the whole mainboard?
Any other ideas?

BTW, this same laptop was doing similar things a few months
back when booted cold but if I rebooted it one more time or so it would
come up ok -- kind of like some circuitry had to warm up to
work ok. It looks like something recently pushed it over the edge
and maybe the video ram went bad.
IBM laptop video can usually be broken down thus: video module, LCD
screen, and voltage inverter. Eliminate the mainboard video module by
attempting to connect a remote monitor: if OK, your onboard video is
good and it's a problem with the inverter board or LCD. Not sure about
the inverter board, but the LCDs are not cheap! If not, it's probably
the mainboard (a slight chance of your vid out port being bad, but
slim). $$$ bucks there, too. Is it under warranty? Major disassembly
is required for both (you must remove the entire LCD panel to repair
the LCD/inverter; and the mainboard is the last component to come out
of the case - full disassembly), but you should be able to find a PDF
for the T41 online, if you have another internet source. IBM
disassembly/reassembly instructions are pretty straightforward, they
tell you what tools you'll need, and what fasteners you'll encounter.
Good luck.
 
M

Mark O. Schlegel

fredman said:
IBM laptop video can usually be broken down thus: video module, LCD
screen, and voltage inverter. Eliminate the mainboard video module by
attempting to connect a remote monitor: if OK, your onboard video is
good and it's a problem with the inverter board or LCD.
I tried connecting my CRT (Mag 800V) to the external vga port, it
looked exactly like the LCD (jumbled pixels). So that implies the
mainboard video is bad right?
Not sure about
the inverter board, but the LCDs are not cheap! If not, it's probably
the mainboard (a slight chance of your vid out port being bad, but
slim). $$$ bucks there, too. Is it under warranty?
Yes, I bought it in May 2004, I think IBM is three years for parts.

Mark
 
F

fredman

I tried connecting my CRT (Mag 800V) to the external vga port, it
looked exactly like the LCD (jumbled pixels). So that implies the
mainboard video is bad right?
It would to me. Accordingly, you need to replace the mainboard. This
can be complicated if you have a security chip on the mainboard
installed. Otherwise, it's a matter of ordering/purchasing a
replacement and carefully making the repair, or have someone do it for
you.
Yes, I bought it in May 2004, I think IBM is three years for parts.
Excellent. Call them and ask how much to send in the whole box and
have them do it for you. It might be worth it, rather than doing the
repair yourself (Dell actually sent a tech out to my sister's house
for mboard replacement, but she had a parts & labor warranty). It
isn't too difficult but some experience is desireable, and of course
the ESD pitfalls increase when dealing with digging a motherboard out
of a case. Good luck.
 
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G

gusdarul

HI
Did you eventually fix your problem? Mine is ThinkPad T41 2379-XX5
it has the same problem. When I booted in first time, it doesn't ge
through the BIOS therefore eventhough I tried to use the externa
monitor, it is still showing the problem. Unfortunatelly, mine is no
under warranty anymore. Now, I am looking for the motherboard if ther
are any....:-

Please be advised for this matter

Thanks
 

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