• Need a new CPU Fan in my old IBM T40 Thinkpad

    Home » Forums » AskWoody support » PC hardware » Questions: What hardware should I get? » Need a new CPU Fan in my old IBM T40 Thinkpad


    The CPU fan sounds like it’s grinding something and I see that CPU fans are still available for this laptop.  I just want to run this by any of the experts here who may have some advice on where to buy a new fan, and what to be on the lookout for.  This is a ca. 2003 IBM T40 ThinkPad laptop that has had a relatively easy life while in my hands.

    I’ve seen the fans at Newegg and that looks like it would be my choice of where to buy, but am open to other suggestions.  I will remove the existing fan, measure it, and maybe even take a picture of it before ordering.  Beyond that, if there’s any other advice anyone can give me I would appreciate it very much.  Thanks.

    Experience is that marvelous thing that enables you recognize a mistake as soon as you make it again.

    Viewing 7 reply threads
    • #2396054

      Can’t offer where to buy it but, I’d get it sooner rather than later 😉
      Is what you are looking at the heatsink/fan combo or just the CPU fan?
      If a replacement heatsink/fan combo remember get some decent thermal paste, makes all the difference in thermal transfer. (I’ve always thrown away the provided and used arctic silver or equivalent pastes)

      WaaS = Windows as a Syphon...suckers!

      2 users thanked author for this post.
      • #2396125

        I was thinking to replace the heatsink/fan unit but I may take another look at that if just the fan can be bought and replaced.  What I need is a good reliable place to purchase from.  Guess I’ll call my brother and see if he still knows any.  He’s retired and doesn’t do much work like this anymore, but it’s worth a try.  Thanks for the tip on the Arctic Silver.

        Experience is that marvelous thing that enables you recognize a mistake as soon as you make it again.

    • #2396064
      1 user thanked author for this post.
      • #2396197

        Yep, the video shows a slightly shortened version of how it’s done.  I put all of the different size screws in separate dixie cups to save time and possible confusion.  IBM makes it easier with symbols on the bottom.  It seems that the fan was black instead of copper the last time I replaced the bios battery.

        I did have another old T40 that needed a whole new system board so I kept it for parts. After I used the HD and removed the RAM and Ultra-Drive unit, I took it to be recycled. I could kick myself now because I didn’t give the fan unit a thought.  That would have made it worth keeping it for.

        Experience is that marvelous thing that enables you recognize a mistake as soon as you make it again.

    • #2396091

      Run the machine briefly before you start to extract the fan (warmth softens the “paste” – which might be a strange waxy concoction you can remould so it melts back flat when you power up, as long as you don’t mix dust into it – scrape that away first).

      If the compound is hard you need to replace it, ask nicely at a TV repair shop for “heatsink paste” to tide you by until you get something more specific. The hard stuff on the sink can be cut back to a useable paste with some effort, but it really needs a tiny dob of Dow Corning DC4 and a lot of mixing to achieve that as it needs to be a “stiff” paste, and DC4 comes in 500 gram tubes so it’s probably a non starter for most. (DC4 does however have another use – to stop car door seals from freezing to the paintwork and keep water out of the HV circuits in our damp locality! )

      Remove the battery as well pack the power pack lead, ground yourself to dissipate static.

      If you are lucky you may find after extracting the unit the fan is attached with three screws and two clips holding it to the metal plate of the cooler, and once its removed the fan may well literally pull from the motor as the motor’s magnet is enough to hold it off the plate. You either need to clean under the fan or possibly straighten the plate fractionally (look for the scuff marks on the plate with a lens to work out the contact areas, bend the plate over a toothpick, not in your hands). If the fan doesn’t pull apart easily do not force anything, instead run a suitable feeler gauge or the edge of a playing card under the edge of the rotor to dislodge the dust there, blow through the cooling vanes to remove the fluff (that is to say, blow towards the fan location), reassemble and reinstall the unit. You can oil the bearing if the unit separates, but only use a tiny drop of 3 in 1 or similar.

      Regardless of repair or replace, The IPDT should confirm if the cooler is working correctly if you are running Windows (though sometimes you may have to check your CPU specs and adjust the tests – mainly you need the load test.) BUT enter the CMOS settings for a minute, check the temperature is sensible there (against the CPU spec) if you can to let the running warmth start the paste flowing before you generate a lot of heat by loading the OS.



      (one of several used, look for TJunction..)



      1 user thanked author for this post.
      • #2396124

        I didn’t consider that the fan could fixed and oiled.  I thought with the age of this laptop, it would be better to replace the fan.  You have got me intrigued now.  If I can fix it and re-paste it, that might be better for the short term.  But will still try to get a new fan if possible.

        Experience is that marvelous thing that enables you recognize a mistake as soon as you make it again.

    • #2396113

      I’ve seen the fans at Newegg and that looks like it would be my choice of where to buy, but am open to other suggestions.

      FWIW, I’d caution you that, at least from one experience I had, some older computer parts from Newegg are provided by the same Chinese manufacturers as those on eBay.

      In June I needed a bottom-case (lower base) for my older HP G6 laptop.  I began by purchasing one on eBay which was labeled “new”.  It came from China after a delay of at least a month and when it arrived the mold that had been used to cast/form it was flawed to the point where the MOBO, the ports and the battery could not be fit into it.

      I decided to go to Newegg and purchase a bottom base from them.  The site labeled it as both new and in stock; it arrived quickly and as scheduled.

      However, that part had exactly the same flaws as did the eBay version; the MOBO, the ports and the battery also could not be fit into it.

      By comparing casting marks, it is certain to me that it had been manufactured from the same flawed pattern/mold as the one from eBay.  So my opinion the Newegg part came from the same plant in China as the eBay one.

      1 user thanked author for this post.
      • #2396122

        I’ve pretty much resigned myself to the fact that the fan/heatsink unit for for this computer is going to be coming from China. I’m going to try to get the right one that fits, and that is my main concern.

        Experience is that marvelous thing that enables you recognize a mistake as soon as you make it again.

    • #2397571

      I found what looks to be the identical fan/heatsink unit at Amazon.  They say it fits T40’s and they recommend Arctic MX-4 heat transfer paste.  Is Arctic Silver better and should I try to find that instead?

      Experience is that marvelous thing that enables you recognize a mistake as soon as you make it again.

    • #2397576

      It’s good assuming it’s the real stuff. https://www.quietpc.com/as5

      Remember less is more.

      That is to say, the purpose of the paste is to interface the surfaces by flowing into and filling the gaps between them to exclude air which is thermally insulating, and replace it with something thermally conductive – you do NOT want any thickness of paste which is why the spec sheet quotes per Mil (as in 0.001 Inch) – basically the heatsink should mainly touch the chip through the paste, not float on a layer of paste, so cleaning the surfaces is important. (Use something plastic, or a fingernail, but never a harder tool if the old paste has set and you have to dig it off – try to drag the debris to the sides of the chip, don’t press the surface down towards the holder any more than you have to. IPA (isopropyl alcohol) softens most of the deposits.) The surfaces involved are machined to a fine tolerance to ensure if you put a small ball of paste in the centre, the parts will press it out correctly if you hold the heatsink in place and level, and tighten the screws in the numbered order working a few turns at each go around the sequence until the mounts meet and the metal springs under the screws are taut, then torque the screws in order (or cross wise if an unmarked four point mounting)..

      Be aware in starting a new tube there may be some paste which has sagged (settled) – that is to say it might be too runny or too thick in the syringe nozzle. If you have only one job maybe discard that tiny bit to be sure you are getting the main body of the paste on the chip.

      There is an old school technique involving seating the heatsink, removing it, and wiping it off before reinstalling to drop the paste thickness. My experience of this is while it works fine for relatively large, coarsely machined heatsinks, you can risk degradation due to tiny bubbles of air drawn into the paste by the vacuum made at the heatsink interface as you remove the sink. So yes for large chips with heat spreaders, maybe only with care for flip chip packages..

      Either way – test it before going too rash and it should be fine, the Intel chips are at least good at preventing damage unless you literally manage to not attach the heatsink properly..

      1 user thanked author for this post.
    • #2397580

      Sorry – completely forgot to compare the two.. but given the age of your machine it was likely it was designed to use a paste sub spec to either candidate so unless your machine overheated by design the paste you choose now isn’t too relevant., but here’s a comparison..


      You could maybe compare the TDP figures for the processors they test and yours in order to deduce a suitable scaling factor to work out what sort of reduction MX4 will give, but I suspect  remembering to ensure the grilles elsewhere are dust free and the rubber feet on the machine haven’t worn down over time bringing the air vents beneath closer to the desk might have an equal beneficial effect.

      1 user thanked author for this post.
    • #2400885

      Okay well the new fan arrived yesterday and I replaced it today.  I followed your instructions oldguy and things seem to have gone well.  Thank you very much oldguy for all the good information because I didn’t get any instructions with the fan, and none with Arctic MX-4.

      The fan runs a little bit on boot-up, then stops and doesn’t start running again for somewhere between a half an hour and 45 mins. This is normal for this laptop that has an Intel Pentium M which I think is a special Pentium 4 for laptops.  Thanks again to everyone for your assistance and info.!

      Experience is that marvelous thing that enables you recognize a mistake as soon as you make it again.

    Viewing 7 reply threads
    Reply To: Need a new CPU Fan in my old IBM T40 Thinkpad

    You can use BBCodes to format your content.
    Your account can't use all available BBCodes, they will be stripped before saving.

    Your information: