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Case study
Specifying durability and repair
for laptop computers
June 2011 A case study of a Hewlett-Packard notebook to
illustrate and encourage the durability and repair of
laptop computers.
Specifying durability and repair for laptop computers 2
Introduction
This case study complements the buying specifications for laptops
that have been developed by WRAP to assist buyers and
manufacturers procure and produce products that last longer, can
be more easily repaired and that lead to lower environmental
impacts.
The HP (Hewlett-Packard) 6530b notebook was used to
demonstrate the practical application of many of these good
practice specifications. The study assesses the key features that
contribute to extending the product‟s lifetime through durability
and repair by highlighting the most beneficial measures, some of
which can be relatively simple to achieve. The buying
specifications (see separate publications) include further detail for
companies wanting to take a more ambitious approach and deliver
greater environmental benefits.
The specifications were developed by assessing a range of laptop
and notebook computers through discussions with manufacturers,
designers and repairers, and also through carrying out „teardown‟
on a range of products to identify design features that facilitate
repair.
Product information
The HP 6530b is a corporate notebook with a widescreen 14”
diagonal display and a dual core processor. It weighs 2.41kg
including the DVD/CD drive. There is an option to install a
webcam and the laptop represents the „high-cost‟ machine and
retails at around £650.
The model comes with a 1 year manufacturer‟s guarantee,
although newer HP corporate models such as the Elitebook series
come with a 3 year parts and labour guarantee. This longer-term
repair warranty typically exceeds that of most models of a similar
specification and helps to ensure that repair takes place in the
event of failure rather than disposal.
Specifying durability and repair for laptop computers 3
Laptop lifetime issues
Due to the mobility of laptops they are more prone to general
damage and hardware failure than desktop models. It is reported
by Square Trade1 that on average 7% of laptops fail due to
hardware malfunction or accidental damage within the first year of
use, however this rises sharply to nearly 20% by year two, and by
the third year one third have failed.
The most common faults and associated issues reported by
independent repairers in the US, relevant studies and by Gartner
IT2 3 and Square Trade4 are:
LCD (liquid crystal display) screens - difficult to remove from
case lids and can break;
lid hinge and bracket damage - due to fatigue by constant use;
hard drive and motherboard (main printed circuit board) faults
DC (direct current) damage to sockets - often plastic
connectors where the power lead is exposed;
overheating of electronic components such as hard-drives and
printed circuit board components;
keyboard damage - particularly individual keys that are not
available to purchase;
cost of key spare parts - such as screens and printed circuit
boards that make repair uneconomical; and
overheating due to insufficient ventilation - often fewer fans
are used due to space restrictions and ventilation slots become
blocked.
Ensuring the reliability of electronic devices is becoming
increasingly challenging, attributable to the rate of technological
advancement and added functionality which can lead to:
increased complexity of electronic circuits;
increased power requirements (e.g. for video); and
new components and material technologies.
Durability
1 http://www.squaretrade.com/pages/laptop-reliability-1109 2 http://www.gartner.com/DisplayDocument?id=493252 3 http://www.gartner.com/press_releases/asset_154164_11.html 4 http://www.squaretrade.com/pages/laptop-reliability-1109
Specifying durability and repair for laptop computers 4
A typical laptop is intended for mobility and is therefore regularly
subject to potential damage by impact, compression loads,
vibration (for example when used on trains) and liquid spillages.
HP‟s product user manual specifies the operating limits for
voltage, temperature, relative humidity, shock and vibration for
safe operation of the laptop, helping the user to reduce potential
damage. The laptop has been designed to withstand these
stresses as far as possible to extend lifetime and reduce the need
for repair.
Mechanical robustness
Vulnerable parts
Design and location of key components is a key consideration to
prevent damage, and hinges of the HP 6530b are positioned away
from its exposed edges and are protected by a cover. The power
socket is recessed on the side of the casing for protection and the
on-off button is away from the edge and close to the keyboard.
Exterior casing
The casing is made from PCABS (a poly-carbonate acrylonitrile
butadiene styrene blend). This is considered to be a robust and
suitable material ideal for this type of application. The polymer is
clearly labelled as shown in figure 1, which assists the recycling
process during disassembly.
The mouldings
are designed to
withstand
breakage and
provide protection
if dropped, and
fixings are located
in areas that are
less prone to
damage such as
away from corners and edges. The wall thickness of the casing is
sufficient to provide good rigidity which reduces flexing during use
Figure 1 Material (PCABS) plastic labelling on casing
Specifying durability and repair for laptop computers 5
and offers protection to internal parts. The covers used for
accessing components are also sufficient to resist flexing and the
laptop shows limited deflection of the top moulding when pressure
is applied around the mouse pad area.
Component housings
All removable parts such as the RAM (random access memory),
hard drive (storage memory) and WLAN (wireless local area
network) module are secured to the casing and have a cover that
is screwed in place. This eliminates the potential for parts to
spring out of their mounts and be exposed to damage.
The touch pad, which undergoes heavy use during the lifetime of
the laptop, is secured with a metal bracket screwed to the chassis
by six bosses.
The main screws securing the two halves of the chassis together
have an adhesive applied to the threads which forms an instant
seal and prevents loosening by vibrations, stress and shock, whilst
also allowing easy disassembly.
Figure 2 Touch pad fixing – from manual
Specifying durability and repair for laptop computers 6
Electrical robustness
Connectors and leads
The keyboard and LED (light emitting diode) boards are connected
to the main circuit board by a ZIF (zero insertion force) connector
which prevents damage caused by applying force upon insertion
and extraction.
All of the connectors
are securely fixed with
the leads routed
around the inside of
the case and clipped or
taped where
necessary. The length
of the wiring between
components is kept to
a minimum to prevent
movement of the
cables, as over time
this may lead to failure of the connectors or soldered joints.
As an example of good practice, the wire clips identified with a “5”
below are used to hold the wire for the wireless antenna cables.
Cooling
The HP model ensures adequate cooling through the use of an
internal fan which draws air in through four underside inlets, and
exhausts warm air through a dedicated slot in the left side
(illustrated as “2” below). Having several air inlets helps to
prevent obstruction when the machine is used on a lap or a
cushion for example.
Figure 3 Wire clip positions – from manual
Figure 4 Side cooling vent – from manual
Specifying durability and repair for laptop computers 7
The fan is controlled by a temperature sensor designed to
automatically operate to protect it from high temperatures. In
order to ensure the air flow is not interrupted, HP recommend
there is a minimum 3” clearance on the left side of the computer
when in use, and that it is placed on a flat surface so the
underside vents are not obstructed.
Repair
Fault diagnosis and technical support
Basic information for the diagnosis of faults is provided by HP in
the user guide and also on a diagnostic page on their website5
which includes information on:
Microsoft Windows error messages;
error conditions such as unexpected shutdowns; and
faults with the display, drives, keyboard and sound.
In addition there is a software diagnostics menu available at start-
up which provides test information on:
start-up: verifies the system components needed for starting
the computer;
run-in: a comprehensive check on system memory; and
hard disk: runs a comprehensive test on all hard drives in the
system.
This allows the user to verify that all the key operating
components are working correctly and identify any faults. Hewlett-
Packard also provides a technical support web centre for this
product6. The self-diagnostic software combined with the
customer support assists users in identifying the cause of an error
and enables them to either take action to remedy the fault or use
the information to inform a repairer.
5http://h20000.www2.hp.com/bizsupport/TechSupport/SupportTaskIndex.jsp?lang=en&cc=uk&prodTypeId=321957&prodSeriesId=3687446&taskId=110
6http://h20000.www2.hp.com/bizsupport/TechSupport/Home.jsp?lang=en&cc=us&prodTypeId=321957&prodSeriesId=3687446&lang=en&cc=us
Specifying durability and repair for laptop computers 8
A comprehensive manufacturer‟s maintenance and service guide
(or manual) can be downloaded7 from HP‟s website to assist
professional repairers and this includes:
exploded views of all the key parts (figure 5);
photographs detailing buttons, sockets and access covers;
illustrated parts catalogues;
sequential parts number listings of available parts;
step-by-step guide to replacing parts;
listing of screw types and locations;
connector pin alignments; and
power cable requirements.
Figure 5 Exploded view of major parts - from manual
7http://bizsupport1.austin.hp.com/bc/docs/support/SupportManual/c01938625/c01938625.pdf
Specifying durability and repair for laptop computers 9
Parts availability
HP‟s online spare parts store8 list prices of available parts.
Availability, together with the price of parts can be a significant
barrier to repair, particularly in the independent repair sector
which deals with repairs undertaken when the guarantee period
has expired. HP facilitate repair by making all parts available for
five years after the model production has ceased.
Access for repair and replacement
The most commonly replaced parts are easily accessible from the
underside of the laptop. Each of the key components can be
accessed by individual panels (figure 6), clearly marked and
referenced in the online user guide9 and the manual.10
Figure 6 Parts access locations - from manual
The panels that allow access to each component are clearly
labelled with a symbol representing the component (below). The
manual also highlights the screws – here a reference key for the
symbols can also assist the process.
8http://h20141.www2.hp.com/hpparts/Default.aspx?mscssid=42DB6E808D6A4E479439E91CF0A70866
9http://h20000.www2.hp.com/bizsupport/TechSupport/DocumentIndex.jsp?lang=en&cc=us&taskId=&contentType=SupportManual&prodSeriesId=3687446&prodTypeId=321957#5
10http://bizsupport1.austin.hp.com/bc/docs/support/SupportManual/c01938625/c01938625.pdf
Specifying durability and repair for laptop computers 10
Figure 7 Screws and associated parts markings (indicated by arrows)
These features make replacement of parts easier and quicker and
while a number of laptop manufactures use similar methods to
access panels, this product demonstrates best practice by also
labelling the covers.
The hard drive, RAM, WLAN and Bluetooth modules, and DVD/CD
drive are all simply secured with screws allowing the repairer to
replace or upgrade the components without the need for specialist
tools. A web page11 on HP‟s site provides a step-by-step guide to
replacing these key components.
Any tools required for disassembly of more complex assemblies
are listed along with recommendations on the handling of
components, cables and connectors to prevent damage including
that from electrostatic discharge. All the parts are described as
safe to replace by a general user, provided the manual guidance
on safe handling of components, cables and connectors is
followed.
To demonstrate the level of ease with which each key part can be
accessed and replaced, as part of the assessment several parts
were replaced following the instructions in the manufacturer‟s user
guide and the process is described below.
11http://h20000.www2.hp.com/bizsupport/site/search/r4_0/jsp/search.jsp?lang=en&cc=uk&prodTypeId=321957&prodSeriesId=3782222&tx=6530b
Specifying durability and repair for laptop computers 11
Hard drive
Two screws secure the hard drive cover to the chassis and a
further screw enables it to be removed from the casing. Four
screws then enable the hard drive to be removed from its
mounting bracket. These stages were found to be simple and
relatively quick, taking less than 5 minutes.
Figure 8 Removal of hard drive – from manual
Bluetooth module
The Bluetooth cover is held in place by a single screw. Beneath
this there is a clip-on lead and the module can then be removed
from the casing. This takes only a minute or two to complete.
DVD/CD drive
Access here is a little more complicated as it requires a Torx
screwdriver. It would be preferable to use the same screws and
screw-head size for all
the covers to avoid tool
changes and decrease
replacement time. Two
further screws then
release the drive from
the retaining bracket
and this takes about 2
minutes to complete.
Figure 9 Removal of Bluetooth cover and module
Specifying durability and repair for laptop computers 12
RAM and WLAN modules
The RAM memory slot and WLAN are easily accessed by the same
cover and one standard screw. The RAM is then simply unplugged
and a replacement inserted. The RAM takes approximately a
minute to replace and the WLAN about 2 minutes.
The WLAN is accessed by two screws and the antenna lead is
removed, and this was found to be a simple operation.
LCD screen
The LCD screen is one of the more complex assemblies to replace,
although the process is simplified by following the step-by-step
guidance in the manual.
In the HP 6530b, the keyboard and switch cover are removed to
access the screen. The screen is then detached from various leads
and its hinges, the screen front bezel, the screen brackets, the
antenna leads and the inverter (screen controller) cable. This
sequence is clearly explained in the manual using text and
photographs and this operation takes around 20 minutes.
Figure 10 Removal of cover for RAM and WLAN Figure 11 Removal of WLAN - from manual
Specifying durability and repair for laptop computers 13
Figure 12 Some of the LCD screen removal stages
While this process is relatively complex it was found to be easier
in the HP model than some of the other manufacturer‟s models
assessed, where the whole keyboard base moulding needed to
be removed to allow access and this should be avoided.
Replacing the LCD screen would be one of the more expensive
tasks carried out by a repairer. A new LCD screen from
independent stockists was found to cost between £75 - 100
(based upon compatible screens from a range of online
vendors.)12
12 http://www.screens4laptops.com/hp_laptop.php, http://www.computerbasement.co.uk/?gclid=COK5uua2oKcCFRAa4QodLU0qYw, http://www.laptop-lcd-screen.co.uk/laptopparts/
Specifying durability and repair for laptop computers 14
Conclusion
The HP 6530b laptop illustrates some of the key specifications that
contribute to durability and repair. This model is designed to be robust and
durable, and also enables many of the major components and assemblies
to be easily removed for replacement or upgrade which is critical to
extending the product‟s life. Parts that would usually need replacement by a
qualified repairer such as the LCD screen, can be replaced by the user
following the clear step-by-step guidance in the manual.
Laptop durability and repair in most cases can be addressed by identifying
and implementing relatively straightforward and „easy to achieve‟
specifications. Measures such as ensuring good availability of spare parts
that are easy to access and replace on the machine can provide significant
benefit and encourage repair and longer product life.
Some „easy to replicate‟ specifications for repair include:
access panels that are clearly labelled and easy to open;
minimising the number of standard screws for access panels and
internal components; and
ensuring the availability of key critical spare parts at reasonable prices.
Enabling user and repairer online access to:
the user guide;
diagnostic information of faults;
detailed parts listings and support; and
step-by-step repair manuals with exploded views and photographs.
Specifying laptops that are robustly constructed, are more durable and last
longer by:
using robust casing and chassis;
protected external parts from damage; and
securely fixing internal components.
Specifying laptops that have good electrical design to reduce the likelihood
of parts failure by:
careful wiring runs and clips;
using zero insertion force connectors;
ensuring adequate component cooling by heat sinks and
thermostatically controlled fans; and
providing adequate air inlets and outlets in considered locations that
prevent obstruction.
While steps have been taken to ensure its accuracy, WRAP cannot accept responsibility or be held liable to any person for loss
or damage arising out of or in connection with this information being inaccurate, incomplete or misleading. This material is
copyrighted. It may be reproduced free of charge subject to the material being accurate and not used in a misleading context.
The source of the material must be identified and the copyright status acknowledged. This material must not be used to
endorse or used to suggest WRAP‟s endorsement of a commercial product or service. For more detail, please refer to our
Terms & Conditions on our website: www.wrap.org.uk
www.wrap.org.uk/retail
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