R31 overheating - solved!

[Keithj]

Ever since I bought it new, three years or so ago, my R31 has suffered from occasional fits of instability. I couldn't work out the reason, and was close to abandoning the ThinkPad. Recently, I found these forums and a thread on fan noise (not a problem I have) with a recommendation for MobileMeter. I installed that, and found that my CPU temperature was all over the map, changing very quickly when a CPU-heavy process started or stopped. It would go from 60 to 80 to 90 degrees C in three "cycles" of MobileMeter refresh.

I thought the symptoms indicated a faulty or blocked fan, and did the usual hefty "blow out" with compressed air. That made no difference at all.

Finally, I decided to risk opening up the R31 to see if the thermal compound between the chip and the heat sink had dried out or crystallised or some such. It was that, or scrap it and buy a new laptop.

My thanks to whoever put the maintenance manual up on the web - that made it easy to dismantle straight to the fan/heatsink/CPU without doing the wrong things.

What I found was a clean, shiny CPU with no thermal compound at all, and a dull dark grey contact area on the fan assembly - also "clean". I smeared it with the "Thermpath" that I use with power transistors in my amateur radio equipment, and reassembled.

The temperature is now stable. It sits at 58 degrees almost all the time, rising to a max of about 80 when I running a stress test. It used to go up to 96 (at which point I stopped things quickly!).

I can only assume that IBM had run out of thermal compound the day they built my R31! Anyway, transistor Thermpath seems to do the job. If the fix deteriorates over time, I'll invest in some higher-quality "heat grease", but for the moment at least I'm happy.

If anyone else has the same problem, I hope this will be some help.

[agarza]

Ideally with a good thermal compound you should get about 45-48C with the fan spinning.

My T42p used at max load would not surpass 62C.
But glad you have your laptop working well. But bare in mind that having your CPU to sustain a high temp all the time should lead to lessen the life of the processor, always try to have it as cool as possible.

[led_snapper]

I have had my R31 apart recently - they apparently use thermal pads when assembled so there isn't the gunky compound or grease - just a fairly hard to get rid of grey residue together with a plastic 'surround' on the heatsink side. If you carefully use acetone on a cotton bud you should be able to remove both, taking GREAT care not to get acetone on any of the plastic elsewhere else it will dissolve it. The cpu's board does seem to be resistant though, at least it was on mine (both my old Celeron processor and the 'new' Pentium III-M. I fully disclaim any responsibility for damage caused by using or abusing the acetone though....

I used a silver based thermal compound on mine and it runs quite happily around 40 deg C or slightly higher with no fan at all.

[Keithj]

Thermal pads would explain it - the heat sink was a dull grey - but there was no sign of anything except a shiny plastic finish on the chip itself. The temperature was all over the place, but far too hot most of the time.

I didn't clean the chip or the heatsink - I'd probably have used isopropanol if I had done so, because that's my usual stuff for cleaning transistors before reapplying Thermpath.

With Thermpath, the R31 is pretty stable between 45 degrees minimum, 60 to 65 max (most of the time), and 52 "ambient". I used Thermpath because that's what I have If I need to do it again (I can't see that as likely), I'll get some "proper" laptop stuff.

The improvement is dramatic!

[led_snapper]

Well pleased you got yours cooler. iso-propanol will shift thermal compound etc and may shift the gunk that was present, but since I tried methanol based optical cleaner, electrical contact cleaner & cellulose thinners - I can't remember whether I did with isopropanol, I can tell you the only thing to really shift the plastic and really tackle the hard ingrained gunk was the acetone (pure from chemists ask at counter). It nicely dissolves the plastic and shifts the adhesive too. Though as I said be careful with the cotton buds not getting any on other parts...

[INTJ]

Just felt compelled to say a big thanks for helping me solve the issue thats been plagueing my R31 for over 2 years. I have been nearly driven out of my mind by this problem.

I had exactly the same problem as you, and was soooo close to buying a new machine when I spotted your post.

I live in Thailand and during the day the room temperature is around 30 degrees. The temperature on my machine with the monitoring program showed it surging to 100+, then the CPU going in to some kind of limp mode running at 166mhz.

As a final, final last ditch attempt to sort it I took it into the local computer shop, he charged me the equivalent of $2 to apply some "silicone" as he called it.

Now the machine runs better than ever, even with midday room temperature 35 degrees it runs at a steady 55, never above 70 even when stressed. No shutdowns, lock ups, slow running.


Now I've got air con running and 2 or 3 applications. 50 degrees, absolutely perfect, and I thank you most sincerely.


Regards,


INTJ.



.

[Keithj]

I'm very pleased it worked for you. I suspect there may be many more R31s out there with the same problem.

"Silicone" covers a multitude of substances, but if it fixed it, your local chap used the right sort!

[awong]

i just found this thread and applied artic silver on my r31 and so far I havent had issues multitasking and running a video off veoh/youtube. Plus I got to take apart my r31 which when I get my wireless antennas I know what to do now.

Using one of the ubuntu temp programs temps seem fine, but I did not get a reading before, i applied the paste, but pc does not seem to bog down as much with having a flash video running