T42 Randomly Shuts Down

[1adam12]

Hello,
I have a 15" T42 laptop Type 2373 that keeps shutting down unexpectedly and without warning. The computer seems to run fine otherwise. I am running XP Pro. Sometimes the laptop will run fine for hours (even days) then other times, it will shut down every few minutes (even before it finishes booting up). It always turns on immediately after it shuts down. I have tried a different hard drive and the same thing still happens.

Due to a previous "Fan Error" message, I have replaced the fan a couple of months ago and even more recently blown it out with compressed air.

I have received clean scans with AVG 2013 free and MalwareBytes Pro.

At this point I am out of ideas and any assistance and/or advice would be highly appreciated.

Thanks!

[RealBlackStuff]

Most likely it is your Southbridge chip going South.
Solution: reball that chip (big Intel chip under the wifi-card), or replace the motherboard.
Happens to a lot of T40/T41/T42 and some T43.
Plenty of threads about this in this Forum.

[1adam12]

Thanks for your reply. In glancing at the Southbridge chip info it appears that a reball means to resolder or replace the chip? It also appears that no one in the US does this or even if it would be worth the price of the repair/replacement? Is a reball an easy fix or would it be better to scrap the laptop and buy a newer model?

[systemBuilder]

A logic board on Ebay is $25-$50, you cannot get a southbridge chip reballed for less than $50.

[1adam12]

Just curious...Is a logic board the same as a motherboard and do I need to be concerned with compatibility or any certain specs? And just exactly what does the southbridge chip do?

Thanks for all the info!

[GACrabill]

Due to a previous "Fan Error" message, I have replaced the fan a couple of months ago and even more recently blown it out with compressed air.

What are your CPU temperatures?
Did you replace the thermal grease on the CPU when you replaced the fan?

[RealBlackStuff]

A "logic board" is what Apple calls a motherboard.
IBM used to call it a "planar".
Everybody else calls this a "motherboard" (or mobo for short).
For a list of compatible/replacement mobos, see my website: www.theboardroom.info/ibm_list.htm
If you open the bottom RAM door on your laptop and remove the RAM module, you should see the mobo P/N or FRU.
In theory you could use any mobo for T40/T41/T42/R50/R51.
BUT: if your LCD is SXGA+ or UXGA, you must use one of the above mobos with ATI graphics.
If XGA, you can also use mobos with Intel graphics.
For the many Southbridge functions, see this: http://forum.thinkpads.com/viewtopic.php?f=2&t=85463

[1adam12]

GACrabill:
I have no idea what my cpu temps are but yes I did use thermal paste when I replaced the fan. Funny thing too is that there was a period of time when I was replacing the fan every few weeks/months because I was receiving a "Fan Error" message on boot-up. I would check the fan and it would not run, so I replaced it. I just figured it was because I was buying used fans and they wouldn't last. The current fan has outlasted the others but now I'm getting the shut down issue. (I think I'd rather have the fan problem because I know how to fix that!!!).

RealBlackStuff:
Thanks for all the interesting info and links! It looks like I have some more work/research to do later.

[spintop]

intermittent hang or shutdown issues could also be caused by unstable voltage to the CPU.
This happened to my T43. I found corrosion on solder joints & components like capacitors and resistors. They affected the stable voltages going to the cpu voltage regulator. I replaced them and its good now.

Is your laptop very old, look out for corrosion near the regulator.

Hope it helps !

[1adam12]

Just wanted to post an update and give my thanks to RealBlackStuff and systemBuilder! I was able to buy a mobo off ebay for $35 and replaced it over last weekend. So far everything is working great! Not the easiest of jobs but I only had 1 small left over part (guess that's why I don't do this for a living !!!!!!). For me, only 1 left over part is beyond fantastic...and so far...No unexpected shutdowns and I have put it through quite a workout.

Thanks again for all the advice and helpful info...I had no clue before I started this thread and probably would have trashed the laptop. Even though it's an older model I love my T42!!!

Wishing everyone a Happy 4th of July!

[emeraldgirl08]

If you are using compressed air to clean out the fan and exhaust locations make sure you use a rigid item (long and thin object) to prevent the fan blades from spinning freely. From what I understand the bearings are not designed for excessive RPMs and will contribute to both faster degradation and earlier replacement. For cleaning I usually pop the keyboard off (only takes ~5 screws to remove) for better access to the innards, stick something in the fan blades, and then use compressed air to remove dust from the fan and exhaust area.

[systemBuilder]

If you are using compressed air to clean out the fan and exhaust locations make sure you use a rigid item (long and thin object) to prevent the fan blades from spinning freely.

Thanks for that, I am in the process of fixing 7 laptops this week and did spin the fans last night on 2x, but will avoid doing that again in the future.

[My_Thinkpad]

Hi there.

Just a thought.... are you running Windows XP?

If you got your Windows OS out of somewhere like Pirate Bay, some of those uploaders like to install tricks to frustrate users.

I had a Windows XP Pro OS from Pirate Bay last week that kept shutting down my Thinkpad X22.

I then replaced that Windows with another one from the same place, and the X22 has worked fine ever since.

Kind regards.