zackbass

Last week my Thinkpad R40 started acting up. It would randomly shut down and often gave the message "fan error" when booting. The fan WAS working normally though. My first thought was a motherboard fan sensing problem sine it was obviously working, but I decided to follow the path of least resistance and do what the IBM service manual said and order a replacement HSF.

It came today and I installed it, but I found something that looked suspiciously like the real problem. The heatsink came off with none of the usual force needed to break the TIM and this is what it looked like:



The CPU was perfectly clean, and the TIM on the HSF was all mushed over to one side. Is this something normal or was this my actual problem?

I finshed replacing HSF and gave it a nice AS Ceramique treatment. I'm running SuperPI right now to see if everything is working right.

jester22c

Yeah that glob on the side of the HSF was probably your culprit, but it never hurts to have a spare HSF on hand. From the picture it almost looks like part of a smushed up packaging peanut lol. Either that or whoever applied the thermal goo at the factory has a lazy eye.

BTW - I work on thinkpads at work (right now) alot and have never seen a fan go out.

gurutoo

Glad you were able to fix it.
Nice photos BTW.

zackbass

I finshed the stress testing and a few restarts and everything seems to be in working order. Is there any chance that the processor (P4M) was throttling because of the heat before the fix?

rockefella

I seem to have the same problem. My Thinkpad R40 will reach the POST and then, an error message - "Fan Error" - will appear, and the computer will power down instead of booting up. Could it be that I have the same problem? Also, what should I do? Do I need to buy a new heatsink and apply new thermal paste? Is this a difficult procedure? Thanks for any help you can give. I've tinkered around with my desktop, but have never dared to mess around with my CPU or my notebook.

Thanks!

zackbass

After some more use of the laptop after doing this fix that seemed to work the problem came back. It seems to be a problem that is out of my reach and I'm going to be sending it back to IBM to get fixed soon. Sorry for the bad news.

jester22c

That's too bad that reseating/regooping didn't work. I'm curious to see what the problem was. Do post back with any updates.

UNCLBEN

I wonder if the HSF mounting mechanism is the cause. If it let the heatsink contact surface get crooked relative to the plane of the CPU die, that could explain the TIM being pushed all over to the side...sort of a "squeegee" effect.

zackbass

Since my 1 year warranty runs out tomorrow I figured I'd give IBM a call yesterday so I could get it fixed in time. Got the usual call direction system for a few layers and then got put on hold for an entirely reasonable couple minutes. The call was directed to a call center in Atlanta GA and I explained what my problem was and that I'd already replaced the HSF so that wasn't the problem (can't let them stick a new HSF in call it done!). The guy was pretty confused that I'd done the repair myself and there were several very long pauses in the conversation while he did something (asked the supervisor about the warranty maybe?), but in the end he said I'd get a box to send the machine to them in a couple days.

Less than 18 hours later I have a box at my garage door. I packed up the laptop with all the necessary info including the all important message that the problem is intermittent and unpredictable, and it's ready to be sent off. I hope their repair techs are half as good as their customer service!