t40 - 2 big problems

[dave111]

Recently I have been having 2 major problems with my t40.

1) When powering on - the screen remains black. not been able to test with an external monitor yet but think that it is a screen problem.

i have to hold power button to turn off and keep retrying to get the screen on.

2) once i have the screen working i login into Windows XP as normal and the system will freeze/lock up at random times.

I am going to try and install a fresh windows XP on a replacement HDD tonight.

Any other suggestions ideas.

are these 2 problems related.

thanks

[rook]

propably GPU may needs reflow,
it often happends.

try to get out top panel with touchpad, push GPU chip hardly and then try to boot up.

[Johan]

Dave:

As rook says above (although not in much detail), particularly T40/T41/T42's are known to suffer from the (in!)famous "loose GPU" problem, which is a situation where the laptop will randomly freeze, boot, not boot etc., and where e.g. touching the laptop may make this happen. The core of it is that the GPU (Graphical Processing Unit) has lost - at times (intermittently) - one or more contacts to the motherboard. This problem is very well known, and many T4x owners have been and/or are troubled about it; read more about this problem and suggested ways to cure it in the threads t42 shuts down when i move it and GUIDE: Reflow GPU fix - 56K WARNING!!! (there are many, many other threads on this forum about this problem - use the "Search" function and see what comes up!).

If you hold your ThinkPad very dear (such as I do with mine!), and if you don't want to try fix it yourself (partly/potential risky business, unless you have the proper equipment and some skills), you may contact e.g. user "jamiphar" of this forum, who offer to repair your GPU problem in a completely professional way - see the thread LCD CCFL Backlight Repair/GPU Rework - I'll fix it for you!

However, before "judging" that you are indeed stuck by the "loose GPU" phenomena, I suggest you calm down for a moment (if not already calm?) and review the thread T42p won't come out of standby or won't boot after shutdown (see the first two suggestions in the post of Sun Feb 10, 2008 6:16 am), as other problems might explain the things you see. Therefore, I suggest you start with investing these, as this is free!

Keep us posted about your progress - I really don't like to see or hear about a nice, trusted ThinkPad going totally out of business...

Johan

[dave111]

Thank you for your message.

I think it is the "loose GPU" phenomena.

If i can get the screen to come on is it worth keeping the laptop ON indefinately?

Is there anyone in London, England who is able to perform the reflow

[Johan]

If i can get the screen to come on is it worth keeping the laptop ON indefinately?

Is there anyone in London, England who is able to perform the reflow

Ad 1) I am not sufficiently qualified to say "yes" to this, but I wouldn't do it if it was my ThinkPad. The "loose GPU" problem is (believed to be) associated with thermal cycling of the GPU; if you shut down the laptop, the GPU will cool down to ambient temperature, and the GPU will then physically contract a small fraction of a millimeter. The motherboard however, will practically remain at ambient temperature, unless some significant heat is dissipated at a local (hot-) spot. When turning on the laptop again, the GPU will heat up above ambient (owing to the power dissipated by the GPU), and this will lead to the GPU physical size will increase a small amount. If the "walk" of the GPU connections to the motherboard is too large, the pads on the motherboard (PCB; printed circuit board) may be "torn apart" from the connections in the PCB (so-called via's, connecting the GPU to other layers in the multi-layer PCB), and the laptop will/may fail again. Same thing happens if you lift your T4x in one of the corners (and particularly if the lid is open!); this will make the PCB "flex" a tiny bit, and this may/will result that the GPU-solder connections to the PCB are torn apart. So, no matter what you do, I believe that the loose GPU problem will trouble you. Keeping the LCD running always will burn out the backlight (CCFL) sooner than necessary, and will also cost life-time on the rest of the system. So, I wouldn’t try to live with an unstable laptop... how do you dare use it, if knowing it is unstable; if you are in the midst of composing a document, and then all of a sudden: Puff! all gone - how fun is that? Go for having this problem permanently and reliably fixed, I'd certainly recommend.

Ad 2) See the post by koobs (of Fri May 30, 2008 1:06 pm), but in in the case of taking this path, you may want first to ask about equipment used, warranty of repair etc.

Johan