Replacing an EEE PC's Fan

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I recently added an EEE PC 900 to my collection of boxen. It's a great little device, but had one fault: a noisy fan; it sounded a bit like something was trailing in the fan blades. Based on this post on the the forum at eeeuser, I guessed that this was probably what the problem was and dismantled my eepsie for a closer look (apparently another user found that, ironically enough, the "Quality Control Passed" sticker was fouling the fan).

Although this article is based on the 900 model, as far as I'm aware this should apply equally to the 700s and most or all of what I say here will also apply to some later models.

The usual disclaimer applies: I'm providing this article in the hope that it will be useful, but can't offer any guarantees or warranties. If you choose to dismantle your EEE PC, be aware that this will void your warranty (if you still have one) and if you don't know what you're doing you may well brick your machine.

While I was at it I thought I might as well take a few photos in case they were useful to anyone else.

(By the way, it turned out that my problem wasn't anything fouling the fan, but an apparently quite common problem with the fan itself; a replacement fan was the solution; these can usually be found on eBay - 700s and 900s use the same type, and it looks like the 1000H has the same one, too).

Getting Started

Before you start, disconnect the power and remove the battery (the battery is released by pushing the two catches on the underside out towards the edges nearest each catch; one will spring back so push back the one that doesn't, then gently pull on the battery and push back the one that does and the battery should come out easily).

Remove the keyboard next. There are three tiny, sprung clips at the top of the keyboard; from left to right, they are near the pipe key (just to the left of F1), between F6 and F7, and between F12 and Pause/Break (this is on the UK model). I've found that, as shown in the picture, a thin and flexible guitar plectrum is great for pushing these back, especially because once you've pushed the clip back you can actually leave the plectrum in place while you tackle the next of the three.

This is fiddly but it doesn't take much force. If you don't have guitar picks lying around, you can use any thin piece of plastic, or even your fingernails (although most people probably won't think leaving their finger nails stuck in there to stop the clips springing back is worth it, heh). Don't use anything metal, it's too likely to damage the casing. Once all three are in, it looks like this:

Now pushing the three picks back will lever the top edge of the keyboard up; it can now easily be lifted away from the machine
at the lower edge:

Notice in particular the ribbon cable connecting the keyboard to the motherboard. The connector has a little plastic clip you can push forward (carefully) at each side, which will encourage it to let go of the cable. Don't pull hard on this; the cable just slides out with no noticeable resistance at all if you've convinced the connector to release correctly. Once this cable is disconnected, the keyboard is free and can be set aside.

Removing the Top Cover

The picture shows the view under the keyboard. The metal sheet directly under the keyboard is part of the top cover; the whole top cover is the next thing to remove. Start by flipping the machine over and undoing the six screws:

(Four along the front edge and one at each of the rear corners). A small amount of reusable adhesive on the end of your screwdriver might help lift the screws out. Of course, loosening them and turning the machine over to let them drop out works too, but be careful not to lose any! (Taking them out one at a time or working on a tidy surface with nowhere for them to roll away to will mitigate the risk).

Next, turn the machine over and remove all visible screws in the area under the keyboard. Remove these carefully (again, some reusable adhesive on the end of a screwdriver is handy to lift them out) and put them somewhere safe.

Once all the screws are out it's possible to prise the top cover off. First, you need to remove the SD card:

Now is a good time to disconnect the track pad too. You can see the connector through a little window in the metal cover; there is a plastic tab on the cable. It's possible to lift the cover first and then remove this, but it's less fiddly to handle this first (and you're less likely to damage the ribbon cable, too). The clip that retains the cable is a smaller version of the same type used to hold the keyboard cable.

Now it's possible to carefully prise off the cover. Guitar picks come in handy for this too; don't use anything metal and you should be able to do this without damaging the plastic. If you run the edge of a guitar pick along the narrow gap between the top and bottom parts of the casing, you can usually find a couple of places that it's relatively easy to slip the pick in. Then, without inserting it too far, you can fairly gently run it along the gap to convince the case to open.

Try to work your way around the case, lifting the edge a little at a time to avoid flexing the plastic too far. Guitar picks, being very thin, make avoiding too much flexing relatively easy. Note: the trackpad is entirely mounted in the top part of the case; the gap runs along underneath the buttons. Don't try to lift the buttons off the casing, they're attached to it!

Certain areas of the join between the top and bottom parts of the casing are easier to slip the pick between; just feel your way around to find the easier locations and work outwards from there, gently lifting the top away. This should never require much force (but don't panic at the quiet 'snapping' sounds; if you're not being too violent with it, these are nothing to worry about).

Note that when you're starting to lift the back edge apart, it helps to have the screen fully open or it will get in the way and stop the back edge spreading apart. Work your way right around the casing edge, including the back (the part usually covered by the battery). Eventually the top of the casing will be released completely and can be lifted away to reveal:

The top of the motherboard. The underside of the top cover looks like this:

Note the three bluish patches; these aid heat transfer into the metal part of the top cover. If they are in poor condition, it would be worth replacing them.

Lifting the Motherboard

To get at the fan, you will need to lift up the motherboard. Look closely at the board and you will notice a few small white connectors; you only need to disconnect the fan and speaker connectors to lift up the board.

The fan connector can be found near the top left corner of the motherboard (the arrow points it out in the picture above). The other white connectors connect the motherboard to the screen; you would need to disconnect these to completely remove the motherboard. To get at the fan, I didn't bother doing this, but some people do advise against my approach, which needs to be done carefully not to damage the screen or the motherboard itself, so it's up to you.

Down near the bottom edge of the motherboard you will find the speaker and battery connectors:

The battery in question is the small 3V CMOS battery, which is actually attached to the underside of your motherboard, so there's no need to disconnect this just to lift the board up (or remove it). The arrow points to the speaker connector; this does need to be disconnected if you want to lift up the motherboard.

Down at the bottom edge you will also notice two little clips that hold the edge of the board. Once you've disconnected the connectors as required, gently push these clips towards the front case edge (they won't move far but will flex a little) to lift the motherboard to reveal:

Notice I'm just tilting the board so that I can leave everything but the speaker and fan connectors connected; this is the lazy and dangerous approach, but if you're careful it's quicker. Be particularly careful not to let the motherboard lean against the screen, and also bear in mind that there's quite a bit of leverage here, so it's easy to apply quite a bit of force to the back corners of the board. Make sure the board corners are free to rotate and don't end up pressing hard against anything as you lift the board up. If you want to be on the safe side, fully disconnect the motherboard and lift it right out; it takes a bit longer but is the more correct approach and certainly eliminates the fiddly process of supporting the EEE PC and motherboard separately while trying to remove the fan's mounting screws and the fan itself.

As you lift the motherboard out, be careful around the connectors; you may need to flex the sides of the case outwards a little to get them out, especially the video and USB ports. If you didn't follow my advice and remove the SD card earlier, this is probably where it will first become really awkward so I hope you did!

Removing the Fan

To get a good look at the state of the fan you'll need to remove it. It's held in there by three small screws. As I say, supporting the machine and motherboard while removing the screws without touching the motherboard to the screen takes a bit of patience. Again, reusable adhesive is a good way to lift the screws out.

The fan has a little rubbery, foamy strip stuck to it; part of this is stuck to the casing. I just carefully cut this to free the fan; the two parts will squeeze back together well enough to form a decent 'seal' anyway so I don't think this will do any harm. If you're very patient you could probably peel it off the case and stick it back, maybe with a bit of extra glue; if you're very conscientious you could actually replace it with a new strip of similar foam.

Reassembly

In true Haynes Manual style, reassembly is the reverse of disassembly! Be careful not to trap any of the wires; you need to pass the fan power connector up through the notch in the motherboard as you put the board back down, and again be careful not to apply any undue force to the board on the way. You'll need to flex the sides of the case out to get the video and USB connectors in.

Make sure the motherboard is properly reseated in its clips at the front of the case and the fan and speaker connectors are reconnected before putting the top cover back on, and be careful not to trap anything (especially under the power button, where there are a couple of small cables that just want to get themselves stuck in there. Note: if it takes any significant amount of force to get the fan or speaker connectors in, do check you're inserting them the right way around as they should be easy enough to connect.

Although it's easier to disconnect the track pad before lifting the top cover off, I found it easier (though still very fiddly) to slip the little ribbon cable in before lowering the cover over it, although I found it was actually easier to push in the connector's clip (to retain the ribbon) after carefully lowering the case top back down. That does mean you have to be careful while lowering it not to knock the loose ribbon back out of the connector, but pushing in the clip with the cover still up and getting the ribbon in after the cover was down both seemed impossible!

The keyboard ribbon is also a pain to get in; I found placing my finger along the edge of the keyboard, gently pushing the ribbon forward to extend it as much as possible, made this as easy as it can be. Remember the retaining clip on the connector on the motherboard needs to be in the 'out' position (released) for the ribbon to go in; the ribbon slides in very easily and should sit straight OK while you push the clip back into place. Then you can just put the three tabs on the front edge of the keyboard into the notches in the case then clip it down.