T23 with video problems. GPU needing a reflow?

[honkbruno]

I have a T23 that is experiencing video problems.

If I put pressure on the bottom of the case a few inches away from the left edge, but in line with the ethernet/modem card, it will boot up fine and can be used. Once I let up on the pressure the mouse cursor freezes and the T23 is unusable. I have to hold down the power button to shut it down.

When the T23 first started acting up it would run okay anywhere from 5 minutes to 45 minutes before locking up. Then, it just got progressively worse.

When powered on, the fan runs and I can hear the hard drive spinning. I tried re-soldering the inductors but that didn't help. (It didn't exhibit inductor problems anyway, I just thought I'd give it a try.) All the connectors are tight, and the RAM and CPU have been reseated.

What could be causing these problems? Does it sound like my GPU could use a re-flow? Thanks!

[rkawakami]

Welcome to thinkpads.com!

I'd say your T23 has another issue, not one related to a loose GPU or inductors (if you also cleaned the metal contacts prior to re-soldering). Try reading this:

http://forum.thinkpads.com/viewtopic.php?t=40648

[honkbruno]

Welcome to thinkpads.com!

I'd say your T23 has another issue, not one related to a loose GPU or inductors (if you also cleaned the metal contacts prior to re-soldering). Try reading this:

http://forum.thinkpads.com/viewtopic.php?t=40648

Thank you! I will check that out tonight and let you know.

[honkbruno]

Welcome to thinkpads.com!

I'd say your T23 has another issue, not one related to a loose GPU or inductors (if you also cleaned the metal contacts prior to re-soldering). Try reading this:

http://forum.thinkpads.com/viewtopic.php?t=40648

I ran the full gamut of PC Doctor tests (thanks to your ISO of the T2X PC Doctor files) and it passed all tests. I'm stumped!

How difficult is it to spot a crack in a solder joint?

[RealBlackStuff]

Very.
Unless you have a 20x or 40x microscope

[rkawakami]

In my case with the two legs of the crystal having cracks in the solder joints, it was very visible even with my half-a-century eyes . I would suggest the following: loop all of the Systemboard tests (or do just one at a time; start with the Real Time Clock test) in PC Doctor while slightly twisting the system or applying pressure on the bottom of the case as you've described. Refer to this post:

http://forum.thinkpads.com/viewtopic.ph ... 065#368065

"Twisting" consists of applying upward pressure beneath the PCMCIA slots and downward pressure at the front left corner or the opposite actions. This technique is useful when encountering inductor problems but also affected my T23 board with the badly soldered crystal.

A question just occurred to me... if all PC Doctor tests passed, did you do anything (or were you doing anything while it was running) which allowed it complete? Conversely, did you move the system at all while the tests were running?

[honkbruno]

In my case with the two legs of the crystal having cracks in the solder joints, it was very visible even with my half-a-century eyes . I would suggest the following: loop all of the Systemboard tests (or do just one at a time; start with the Real Time Clock test) in PC Doctor while slightly twisting the system or applying pressure on the bottom of the case as you've described. Refer to this post:

http://forum.thinkpads.com/viewtopic.ph ... 065#368065

"Twisting" consists of applying upward pressure beneath the PCMCIA slots and downward pressure at the front left corner or the opposite actions. This technique is useful when encountering inductor problems but also affected my T23 board with the badly soldered crystal.

A question just occurred to me... if all PC Doctor tests passed, did you do anything (or were you doing anything while it was running) which allowed it complete? Conversely, did you move the system at all while the tests were running?

What I thought was ALL of the PC Doctor tests was actually only the System Board Tests. And they passed without any manipulation of the motherboard. However, I've now noticed that I have to flex the MB (hold the case by the left corner farthest away from the LCD) in between tests otherwise I can't select the different tests and the laptop just beeps in objection at me. I also have to flex the MB just to get PC Doctor to load upon startup. The tests seem to run fine though once started.

I started running some more tests this morning while getting ready for work and the following two video tests failed:
S3 2D Engine Test
S3 3D Engine Test

It did pass the other video tests.

[rkawakami]

Interesting... if the video tests are the only diagnostics that are failing in PC Doctor, then you just might have a loose GPU. Besides the inductor(s) causing weird startup/running problems, I've seen both the aforementioned crystal and bad memory slots being the source of T23 intermittent hangs while the system is moved or otherwise pressured in certain areas.

It might be a good idea to grab a copy of memtest86+ and verify that your module(s) and SODIMM slots are okay. If you have two modules installed, test them one at-a-time. Allow at least three passes (about 2 hours for a 512MB stick) for each module and test it separately in both slots. While the diagnostic is running, move the system around and flex the chassis to see if that causes any errors.

http://www.memtest.org/

If it turns out that the module(s) are fine and you don't appear to have any bad memory slots and PC Doctor doesn't fail anything other than some of the video tests, then the two solutions are to attempt a re-flow or swap out the motherboard.