Releasing Daemons: September 2010

In this post I'll describe how a Sony Vaio VGN-Z590 laptop can be disassembled in order to clean its heatsink and renew CPU or other chips' thermal grease.

Make sure you have a set of jeweler's screwdrivers, a set of flat-tip and Philips screwdrivers and sufficient amount of CPU thermal compound. Also read the text thoroughly to understand if you need anything else.

Note that preview pictures within this post are not only scaled down but also truncated from either side by Google Picasa and my circle or box markings are not always visible so you need to click on a photo to see it full size.

Okay, let's start with it. Shut down the computer, disconnect the DC power adaptor and remove the battery. Place the unit upside down.

Remove the 7 screws right on the bottom (red) and the 2 screws in the battery compartment (green). Then unscrew the memory lid (left yellow circle) and remove it, underneath the lid there’s the last screw securing the housing, remove that screw.

Turn the laptop over and open the lid fully. There’s a series of latches (red in the picture below) and metal hooks holding the keyboard panel along the left, right and front side of the housing. Use your nails or a plastic ruler to insert it between the keyboard panel and the middle frame and gently release the keyboard panel.

[ The middle frame is the grey colored panel containing the battery, HDD and wireless LEDs on the front side of the housing. ]

After the keyboard panel has been released you can lift it up however there’s the keyboard ribbon cable still holding it. Unplug its connector from the mainboard and finally remove the keyboard.

Next you will need to remove the middle frame. Note that the middle frame is a plastic structure of variable thickness, in some points very thin. A part of the middle frame contains an aluminum bracket attached to other parts by plastic rivets. So you must be very cautious when removing the middle frame.

First unscrew the 3 black screws (green in the photo below) holding the HDD and DVD drive and one another black screw next to the bigger HDD bracket (blue). Then remove the 2 silver screws next to the speakers (encircled by red). Next disconnect the HDD and DVD drive connectors from the mainboard (yellow) by gently pulling them up.

To remove the DVD drive you need to open its door. To do this with no electrical power supplied take a needle, insert it in the small hole (marked in the photo below) and push. The door will open. Pull the DVD drive carefully out of the housing.

Next remove the HDD along with the two aluminum mounting brackets holding it (red in the photo below) and the black rubber gaskets on its corners. Note that the brackets are captured by the series of plastic latches (green) which are below the HDD level and are not visible. Therefore you need to push up gently the entire assembly while rocking it slightly. Probably you’ll need an assistance of a flat-tip screwdriver to release the latches when you figure out where they are and how they hold the assembly.

What is still holding the middle frame are the latches next to laptop lid hinges. Two of these latches are covered with the two barrel-shaped side caps (shown in the photo below): one at the DC jack side and the other at the power button side.

To remove them use a bamboo skewer or flat-tip screwdriver, tip wrapped with one layer of soft insulation tape. These will let you avoid scratches and dents when you push the caps by the inner side in the directions indicated by the arrows in the picture above. See the following photo to understand where the latches are located inside the caps.

Once you removed the barrel caps you are able to release the following 3 latches (those two which were covered by barrel caps + one more) using a screwdriver or a thin ruler:

Then unplug the three white connectors indicated in the photo below. To do this grab the wire next to the connector and pull it carefully upwards gradually applying more and more force until the connector goes out of the socket.

Pull the cable corresponding to the biggest white connector out of the groove inside the middle frame (long box in the picture below). Then pull up the small ribbon cable (the small box in the lower left part of the picture below).

Now you can lift the middle frame and disconnect the ribbon cable still tying it to the mainboard by gently pulling it upwards (the box at the right in the picture below):

The middle frame is completely removed. Next we will release the mainboard.

Unplug the two white connectors (the two boxes at the left in the photo above).

Then disconnect from the motherboard the 5 ribbon cables marked with green in the photo below. To do so lift the small wide lock going at the top of the socket. This will release the ribbon cable. To release the sixth cable connecting the card reader board first you will need to remove the screw attaching the board to the housing. When you finished detach the ribbon cable as you did to other five ribbon cables. The card reader board cable and its screw are encircled with blue in the picture below.

Disconnect the 2 antenna cables (green in the picture below) by pulling them up off the antenna jacks. Release the light gray one from under the 2 adhesive tape pieces covering it (marked with yellow boxes). Then unscrew the female screw and the black screw (encircled with red).

Remove the 2 screws fixing the fan (green in the picture below). Lift up the phone jack (red) from the chamber in the housing. Now you can lift a bit the mainboard. Then you can detach the ribbon cable (marked with blue) connecting the network I/O board from the mainboard using the same technique you have used for other ribbon cables surrounding the mainboard.

At this point we’ve finished releasing the mainboard. We won’t disconnect it entirely.

Open the laptop’s lid to the maximum. Take a layer of thick cloth or soft packaging material and put it onto the LCD screen to prevent it from scratches. Then turn the mainboard around the wires still connecting it to the housing and lay it down to the screen.

There are 3 silver screws attaching the heatsink to the mainboard. Unscrew them:

Turn the heatsink assembly to the left around the adhesive tape glued to the heatsink exhaust and the fan. (we won’t remove this tape also.) While doing this be careful and apply moderate force as former thermal compounds can take some time to release the heatsink. Overly pulling the heatsink assembly can damage the chips it is attached to. If the heatsink can’t be released by a moderate force than use a hairdryer to make the old compound softer and then you will be able to detach the heatsink assembly from the chips easily.

The following photo shows the heatsink assembly opened. As you can see this side of the assembly covers the two chips.

After the heatsink assembly is opened you can begin cleaning. Vacuum clean the vents and the fan. Also you may use Q-tips to reach inaccessible areas. Clean until no considerable amount of dust left.

What is good for this laptop model is that the CPU has not to be removed from its socket in order to renew thermal compound. This minimizes the risk of damaging CPU’s pins and the CPU socket.

Remove the old pieces of thermal compound from the chips and corresponding heatsink areas. Finish by perfectly cleaning the surfaces with cotton swabs soaked in acetone or 99% alcohol.

Apply sufficient amount of thermal compound on each chip and evenly distribute it over the whole surface:

At this point the heatsink maintenance is over.

Flip the heatsink assembly back to its place and replace the three heatsink screws. Then repeat the whole disassembly process in the opposite order.
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