HP ProDesk 480 G2, ProDesk 400 G2, ProDesk 490 G2 Maintenance And Service Manual

Maintenance and Service Guide

HP ProDesk 400 G2 Microtower
HP ProDesk 480 G2 Microtower
HP ProDesk 490 G2 Microtower

© Copyright 2014 Hewlett-Packard
Development Company, L.P. The information
contained herein is subject to change without
notice.

Intel and Pentium are trademarks of Intel
Corporation in the U.S. and other countries.
Bluetooth is a trademark owned by its
proprietor and used by Hewlett-Packard
Company under license. Microsoft, Windows,
WIndows 7, and Windows 8 are U.S. registered
trademarks of the Microsoft group of
companies. SD Logo is a trademark of its
proprietor.

The only warranties for HP products and
services are set forth in the express warranty
statements accompanying such products and
services. Nothing herein should be construed
as constituting an additional warranty. HP shall
not be liable for technical or editorial errors or
omissions contained herein.

This document contains proprietary
information that is protected by copyright. No
part of this document may be photocopied,
reproduced, or translated to another language
without the prior written consent of Hewlett­Packard Company.

First Edition (July 2014)

Document Part Number: 762902-001

Product notice

This guide describes features that are common
to most models. Some features may not be
available on your computer.

Not all features are available on all editions of
Windows 8. This computer may require
upgraded and/or separately purchased
hardware, drivers, and/or software to take full
advantage of Windows 8 functionality. See

http://www.microsoft.com for details.

This computer may require upgraded and/ or
separately purchased hardware and/or a DVD
drive to install the Windows 7 software and
take full advantage of Windows 7 functionality.
See http://windows.microsoft.com/en-us/

windows7/get-know-windows-7 for details.

Safety warning notice

WARNING! To reduce the possibility of heat-related injuries or of overheating the device, do not place

the device directly on your lap or obstruct the device air vents. Use the device only on a hard, flat surface. Do
not allow another hard surface, such as an adjoining optional printer, or a soft surface, such as pillows or
rugs or clothing, to block airflow. Also, do not allow the AC adapter to contact the skin or a soft surface, such
as pillows or rugs or clothing, during operation. The device and the AC adapter comply with the user­accessible surface temperature limits defined by the International Standard for Safety of Information
Technology Equipment (IEC 60950).

iii

iv Safety warning notice

Table of contents

1 Product features ........................................................................................................................................... 1

Standard configuration features ........................................................................................................................... 1

Front panel components ....................................................................................................................................... 2

Rear panel components — HP ProDesk 400 G2 and 480 G2 models ................................................................... 3

Rear panel components — HP ProDesk 490 G2 models ...................................................................................... 4

Serial number location .......................................................................................................................................... 5

2 Activating and Customizing the Software ........................................................................................................ 6

Activating and customizing the software in Windows 7 ....................................................................................... 6

Activating the Windows operating system ......................................................................................... 6

Downloading Windows 7 updates ....................................................................................................... 6

Installing or upgrading device drivers ................................................................................................ 7

Customizing the monitor display ........................................................................................................ 7

Activating and customizing the software in Windows 8 ....................................................................................... 7

Activating the Windows Operating System ........................................................................................ 7

Downloading Windows 8 updates ....................................................................................................... 7

Customizing the monitor display ........................................................................................................ 8

3 Illustrated parts catalog ................................................................................................................................ 9

Computer major components ................................................................................................................................ 9

Cables ................................................................................................................................................................... 12

Misc parts ............................................................................................................................................................. 13

Drives ................................................................................................................................................................... 15

PCI boards ............................................................................................................................................................ 16

4 Routine care, SATA drive guidelines, and disassembly preparation .................................................................. 17

Electrostatic discharge information ................................................................................................................... 17

Generating static ............................................................................................................................... 17

Preventing electrostatic damage to equipment .............................................................................. 18

Personal grounding methods and equipment .................................................................................. 18

Grounding the work area .................................................................................................................. 18

Recommended materials and equipment ........................................................................................ 19

Operating guidelines ........................................................................................................................................... 19

Routine care ......................................................................................................................................................... 20

General cleaning safety precautions ................................................................................................ 20

Cleaning the Computer Case ............................................................................................................. 20

v

Cleaning the keyboard ...................................................................................................................... 20

Cleaning the monitor ......................................................................................................................... 21

Cleaning the mouse ........................................................................................................................... 21

Service considerations ........................................................................................................................................ 21

Power supply fan ............................................................................................................................... 21

Tools and software Requirements ................................................................................................... 21

Screws ............................................................................................................................................... 22

Cables and connectors ...................................................................................................................... 22

Hard Drives ........................................................................................................................................ 22

Lithium coin cell battery ................................................................................................................... 22

SATA hard drives .................................................................................................................................................. 23

SATA hard drive cables ........................................................................................................................................ 23

SATA data cable ................................................................................................................................. 23

SMART ATA drives ................................................................................................................................................ 23

Cable management .............................................................................................................................................. 23

5 Removal and replacement procedures: Microtower ........................................................................................ 25

Preparation for disassembly ............................................................................................................................... 25

Access panel ........................................................................................................................................................ 26

Front bezel ........................................................................................................................................................... 27

Optical drive bezel blank ..................................................................................................................................... 28

Memory ................................................................................................................................................................ 29

DIMMs ................................................................................................................................................ 29

DDR3-SDRAM DIMMs ......................................................................................................................... 29

Populating DIMM sockets (HP ProDesk 400 G2 and 480 G2 models) .............................................. 30

Populating DIMM sockets (HP ProDesk 490 G2 models) .................................................................. 30

Installing DIMMs ................................................................................................................................ 31

Expansion cards ................................................................................................................................................... 32

Drives ................................................................................................................................................................... 36

Drive positions ................................................................................................................................... 38

Removing a slim optical drive ........................................................................................................... 39

Installing a slim optical drive ............................................................................................................ 39

Removing a 3.5-inch hard drive ........................................................................................................ 41

Installing a 3.5-inch hard drive ......................................................................................................... 42

Removing a 2.5-inch hard drive ........................................................................................................ 43

Installing a 2.5-inch hard drive ......................................................................................................... 44

WLAN module ...................................................................................................................................................... 45

RTC battery .......................................................................................................................................................... 48

DisplayPort connector module ............................................................................................................................ 50

Front I/O and power switch assembly ................................................................................................................. 51

Fan sink ................................................................................................................................................................ 54

vi

Processor ............................................................................................................................................................. 56

Speaker ................................................................................................................................................................ 58

Fan ....................................................................................................................................................................... 60

Power supply ....................................................................................................................................................... 62

System board ....................................................................................................................................................... 66

HP ProDesk 400 G2 system board callouts ...................................................................................... 68

HP ProDesk 480 G2 system board callouts ...................................................................................... 69

HP ProDesk 490 G2 system board callouts ...................................................................................... 71

6 Computer Setup (F10) Utility ........................................................................................................................ 73

Computer Setup (F10) Utilities ............................................................................................................................ 73

Using Computer Setup (F10) Utilities ............................................................................................... 74

Computer Setup—File ...................................................................................................................... 75

Computer Setup—Storage ............................................................................................................... 76

Computer Setup—Security ............................................................................................................... 77

Computer Setup—Power .................................................................................................................. 80

Computer Setup—Advanced ............................................................................................................ 81

Recovering the Configuration Settings ............................................................................................................... 82

7 Troubleshooting without diagnostics ............................................................................................................ 83

Safety and comfort .............................................................................................................................................. 83

Before you call for technical support .................................................................................................................. 83

Helpful hints ........................................................................................................................................................ 84

Solving general problems ................................................................................................................................... 85

Solving power problems ...................................................................................................................................... 89

Solving hard drive problems ............................................................................................................................... 90

Solving media card reader problems .................................................................................................................. 92

Solving display problems .................................................................................................................................... 93

Solving audio problems ....................................................................................................................................... 97

Solving printer problems ..................................................................................................................................... 99

Solving keyboard and mouse problems ........................................................................................................... 100

Solving Hardware Installation Problems .......................................................................................................... 102

Solving Network Problems ................................................................................................................................ 104

Solving memory problems ................................................................................................................................ 108

Solving processor problems .............................................................................................................................. 109

Solving CD-ROM and DVD problems ................................................................................................................. 110

Solving USB flash drive problems ..................................................................................................................... 112

Solving front panel component problems ........................................................................................................ 112

Solving Internet access problems ..................................................................................................................... 113

Solving software problems ............................................................................................................................... 114

vii

8 POST error messages ................................................................................................................................. 116

POST numeric codes and text messages .......................................................................................................... 116

Interpreting POST diagnostic front panel LEDs and audible codes .................................................................. 123

9 Password security and resetting CMOS ........................................................................................................ 126

Resetting the password jumper ........................................................................................................................ 126

Changing a Setup or Power-On password ........................................................................................................ 127

Deleting a Setup or Power-On password .......................................................................................................... 128

Clearing and resetting the CMOS ....................................................................................................................... 128

10 HP PC Hardware Diagnostics ..................................................................................................................... 130

Why run HP PC Hardware Diagnostics .............................................................................................................. 130

How to access and run HP PC Hardware Diagnostics ....................................................................................... 130

Downloading HP PC Hardware Diagnostics (UEFI) to a USB device .................................................................. 130

11 System backup and recovery .................................................................................................................... 132

Backing up, restoring, and recovering in Windows 8.1 or Windows 8 ............................................................. 132

Creating recovery media and backups ........................................................................................... 132

Restoring and recovering using Windows tools ............................................................................. 132

Using Reset when the system is not responding ......................................................... 133

Recovery using the Windows recovery USB flash drive ............................................... 133

Recovery using Windows operating system media (purchased separately) .............. 134

Backing up, restoring, and recovering in Windows 7 ........................................................................................ 134

Creating recovery media ................................................................................................................. 135

Creating recovery media using HP Recovery Manager (select models only) .............. 135

Creating recovery discs with HP Recovery Disc Creator (select models only) ............ 136

Creating recovery discs .............................................................................. 136

Backing up your information ........................................................................................ 137

System Restore ............................................................................................................................... 137

System Recovery ............................................................................................................................. 138

System Recovery when Windows is responding .......................................................... 138

System Recovery when Windows is not responding ................................................... 139

System Recovery using recovery media (select models only) .................................... 139

Using HP Recovery Disc operating system discs (select models only) ....................... 140

Appendix A Power cord set requirements ....................................................................................................... 142

General requirements ....................................................................................................................................... 142

Japanese power cord requirements ................................................................................................................. 142

Country-specific requirements ......................................................................................................................... 143

viii

Appendix B Statement of Volatility ................................................................................................................ 144

Appendix C Specifications ............................................................................................................................. 146

Index ........................................................................................................................................................... 148

ix

x

1 Product features

Standard configuration features

Features may vary depending on the model. For support assistance and to learn more about the hardware
and software installed on your computer model, run the HP Support Assistant utility.

Standard configuration features 1

Front panel components

Drive configuration may vary by model. Some models have a bezel blank covering the optical drive bay.

1 Slim Optical Drive (optional) 5 Hard Drive Activity Light

2 Dual-State Power Button 6 USB 3.0 Ports (blue)

3 Microphone Connector 7 Headphone Connector

4SD Card Reader

NOTE: The Power On Light is normally white when the power is on. If it is flashing red, there is a problem with the

computer and it is displaying a diagnostic code.

2 Chapter 1 Product features

Rear panel components — HP ProDesk 400 G2 and 480 G2
models

1 Power Cord Connector 7 Line-Out Connector for powered audio

devices (green)

2

Line-In Audio Connector (blue) 8 DVI-D Monitor Connector

3

VGA Monitor Connector 9 USB 2.0 Ports (black)

4

RJ-45 Network Connector 10 Serial Connector

5

PS/2 Mouse Connector (green) 11 PS/2 Keyboard Connector (purple)

6 Voltage Select Switch (included on some models

only)

NOTE: An optional second serial port and an optional parallel port are available from HP.

When a graphics card is installed in one of the system board slots, the video connectors on the graphics card and the
integrated graphics on the system board may be used at the same time. However, for such a configuration, only the display
connected to the discrete graphics card will display POST messages.

The system board graphics can be disabled by changing settings in Computer Setup.

Rear panel components — HP ProDesk 400 G2 and 480 G2 models 3

Rear panel components — HP ProDesk 490 G2 models

1 Power Cord Connector 7 Line-Out Connector for powered audio

devices (green)

2

Line-In Audio Connector (blue) 8 DVI-D Monitor Connector

3

VGA Monitor Connector 9 USB 2.0 Ports (black)

4

RJ-45 Network Connector 10 USB 3.0 Ports (blue)

5

PS/2 Mouse Connector (green) 11 Serial Connector

6 Voltage Select Switch (included on some models

only)

12

PS/2 Keyboard Connector (purple)

NOTE: An optional second serial port and an optional parallel port are available from HP. Some models have an optional

DisplayPort on the rear panel.

When a graphics card is installed in one of the system board slots, the video connectors on the graphics card and the
integrated graphics on the system board may be used at the same time. However, for such a configuration, only the display
connected to the discrete graphics card will display POST messages.

The system board graphics can be disabled by changing settings in Computer Setup.

4 Chapter 1 Product features

Serial number location

Each computer has a unique serial number and a product ID number that are located on the exterior of the
computer. Keep these numbers available for use when contacting customer service for assistance.

Serial number location 5

2 Activating and Customizing the Software

NOTE: This chapter provides information for both Windows 7 and Windows 8.

Activating and customizing the software in Windows 7

If your computer was not shipped with a Windows® operating system, some portions of this documentation
do not apply. Additional information is available in online help after you activate the operating system.

CAUTION: Do not add optional hardware or third-party devices to the computer until the operating system

is successfully activated. Doing so may cause errors and prevent the operating system from installing
properly.

NOTE: Be sure there is a 10.2 cm (4 inch) clearance at the back of the unit and above the monitor to permit

the required airflow.

Activating the Windows operating system

The first time you turn on the computer, the operating system is set up and activated automatically. This
process takes about 5 to 10 minutes. Carefully read and follow the instructions on the screen to complete the
activation.

We recommend that you register your computer with HP during operating system setup so you can receive
important software updates, facilitate support questions, and sign up for special offers.

CAUTION: After the activation process has begun, DO NOT TURN OFF THE COMPUTER UNTIL THE PROCESS IS

COMPLETE. Turning off the computer during the activation process may damage the software that runs the
computer or prevent its proper installation.

NOTE: If the computer shipped with more than one operating system language on the hard drive, the

activation process could take up to 60 minutes.

Downloading Windows 7 updates

Microsoft may release updates to the operating system. To help keep the computer running optimally, HP
recommends checking for the latest updates during the initial installation and periodically throughout the life
of the computer.

1. To set up your Internet connection, click Start > Internet Explorer and follow the instructions on the

screen.

2. After an Internet connection has been established, click the Start > All Programs > Windows Update.

3. Run Windows Update monthly thereafter.

6 Chapter 2 Activating and Customizing the Software

Installing or upgrading device drivers

When installing optional hardware devices after the operating system installation is complete, you must also
install the drivers for each of the devices.

In Windows 7, if prompted for the i386 directory, replace the path specification with C:\i386, or use the
Browse button in the dialog box to locate the i386 folder. This action points the operating system to the

appropriate drivers.

Obtain the latest support software, including support software for the operating system, from

http://www.hp.com/support. Select your country and language, select Download drivers and software (and

firmware), enter the model number of the computer, and press Enter.

Customizing the monitor display

If you wish, you can select or change the monitor refresh rates, screen resolution, color settings, font sizes,
and power management settings.

For more information, refer to the online documentation provided with the graphics controller utility or the
documentation that came with your monitor.

Right-click on the Windows desktop, then click Personalize to change display settings.

Activating and customizing the software in Windows 8

Additional information is available in online help after you activate the operating system.

NOTE: Be sure there is a 10.2 cm (4 inch) clearance at the back of the unit and above the monitor to permit

the required airflow.

Activating the Windows Operating System

The first time you turn on the computer, the operating system is set up and activated automatically. This
process takes about 5 to 10 minutes. Carefully read and follow the instructions on the screen to complete the
activation.

We recommend that you register your computer with HP during operating system set up so you can receive
important software updates, facilitate support questions, and sign up for special offers. You can also register
your computer with HP using the Register with HP app on the Start screen.

CAUTION: After the activation process has begun, DO NOT TURN OFF THE COMPUTER UNTIL THE PROCESS IS

COMPLETE. Turning off the computer during the activation process may damage the software that runs the
computer or prevent its proper installation.

Downloading Windows 8 updates

Microsoft may release updates to the operating system. To help keep the computer running optimally, HP
recommends checking for the latest updates during the initial installation and periodically throughout the life
of the computer.

Run Windows Update as soon as possible after you set up your computer.

1. Point to the upper-right or lower-right corner of the Start screen to display the charms.

2. Click Settings > Change PC Settings > Windows Update.

3. Run Windows Update monthly thereafter.

Activating and customizing the software in Windows 8 7

Customizing the monitor display

You can customize display settings for Windows 8 separately for the Start screen and the Desktop.

To customize the Start screen:

1. Point to the upper-right or lower-right corner of the Start screen to display the charms.

2. Click Settings > Change PC Settings.

3. Click Personalize to change the display settings.

To customize the Desktop:

1. Click the Desktop app on the Start screen.

2. Right-click on the desktop, and then click Personalize to change display settings.

8 Chapter 2 Activating and Customizing the Software

3 Illustrated parts catalog

NOTE: HP continually improves and changes product parts. For complete and current information on

supported parts for your computer, go to

http://partsurfer.hp.com, select your country or region, and then

follow the on-screen instructions.

Computer major components

Computer major components 9

Item Description

(1) Front bezel

For use in all countries and regions except for the People’s Republic of China

For use in the People’s Republic of China

(2) Access panel

Power supply

(3) 300W, regular

300W, Energy Star 5.0

300W, Active PFC + SEPA

300W, Active PFC

(4) 180W, regular

180W, Energy Star 5.0

180W, Active PFC

(5) Memory modules (PC3,12800, CL11)

8-GB

4-GB

2-GB

System board (includes replacement thermal material)

(6) HP ProDesk 400 models:

●

Without Windows 8.1

●

Windows 8.1 Standard

●

Windows 8.1 Professional

●

NetClone (the People’s Republic of China only)

(7) HP ProDesk 480 models:

●

Without Windows 8.1

●

Windows 8.1 Standard

●

Windows 8.1 Professional

●

NetClone (the People’s Republic of China only)

(8) HP ProDesk 490 models:

●

Without Windows 8.1

●

Windows 8.1 Standard

●

Windows 8.1 Professional

●

NetClone (the People’s Republic of China only)

Processors (include replacement thermal material; not illustrated)

Intel Core i7 4790 (3.6-GHz, 6-MB L3 cache)

10 Chapter 3 Illustrated parts catalog

Item Description

Intel Core i7 4790S (3.2-GHz, 6-MB L3 cache)

Intel Core i7 4771 (3.5-GHz, 8-MB L3 cache)

Intel Core i7 4770 (3.4-GHz, 8-MB L3 cache)

Intel Core i7 4770s (3.1-GHz, 8-MB L3 cache)

Intel Core i5 4690 (3.5-GHz, 6-MB L3 cache)

Intel Core i5 4690S (3.2-GHz, 6-MB L3 cache)

Intel Core i5 4670 (3.4-GHz, 6-MB L3 cache)

Intel Core i5 4670s (3.1-GHz, 6-MB L3 cache)

Intel Core i5 4590 (3.3-GHz, 6-MB L3 cache)

Intel Core i5 4590S (3.0-GHz, 6-MB L3 cache)

Intel Core i5 4570 (3.2-GHz, 6-MB L3 cache)

Intel Core i5 4570s (2.9-GHz, 6-MB L3 cache)

Intel Core i5 4430 (3.0-GHz, 6-MB L3 cache)

Intel Core i5 4430s (2.7-GHz, 6-MB L3 cache)

Intel Core i3 4360 (3.7-GHz, 4-MB L3 cache)

Intel Core i3 4350 (3.6-GHz, 4-MB L3 cache)

Intel Core i3 4340 (3.6-GHz, 4-MB L3 cache)

Intel Core i3 4330 (3.5-GHz, 4-MB L3 cache)

Intel Core i3 4150 (3.5-GHz, 4-MB L3 cache)

Intel Core i3 4130 (3.4-GHz, 4-MB L3 cache)

Intel Pentium G3450 (3.4-GHz, 3-MB L3 cache)

Intel Pentium G3440 (3.3-GHz, 3-MB L3 cache)

Intel Pentium G3430 (3.3-GHz, 3-MB L3 cache)

Intel Pentium G3420 (3.2-GHz, 3-MB L3 cache)

Intel Pentium G3240 (3.1-GHz, 3-MB L3 cache)

Intel Pentium G3220 (3.0-GHz, 3-MB L3 cache)

Intel Celeron G1850 (2.9-GHz, 2-MB L3 cache)

Intel Celeron G1840 (2.8-GHz, 2-MB L3 cache)

Computer major components 11

Cables

Item Description

(1) SATA data cable, hard drive, 10 inch, two straight ends

(2) SATA data cable, 10 inch, one straight end, one right angled end

SATA data cable, 14 inch, one straight end, one right angled end

SATA data cable, 14 inch, one straight end, one right angled end

DisplayPort cable

DMS-59 to dual VGA cable

DMS-59 to dual DVI cable

Adapters

USB 3.0-to-USB 2.0 (200 mm)

USB 3.0-to-USB 2.0 (China only)

DisplayPort to VGA

DisplayPort to DVI

DisplayPort to HDMI

DVI to VGA

DVI-I to VGA (BFR/PVC free)

DVI-I to VGA (Standard)

12 Chapter 3 Illustrated parts catalog

Misc parts

Item Description

(1) Fan sink (includes replacement thermal material)

Standard

BFR/PVC free

(2) Speaker

(3) Fan

Standard

Non-recycled

(4) Front I/O assembly

(5) Fan vent cover for use in models without a chassis fan

WLAN modules

Misc parts 13

Item Description

HP WLAN 802.11 a/b/g/n + Bluetooth 4.0

Intel Dual Band Wireless-N 7260NB 802.11 a/b/g/n 2x2 WiFi + BT4.0

Card reader

Optical drive bezel blank

Grommet (hard drive screw, blue)

WLAN antennas

Clamp lock

HP Ultraslim Keyed Cable Lock

Drive adapters:

Hard drive carrier, 2.5-inch to 3.5-inch

Drive adapter, 2.5-inch

Removable frame carrier (installs in optical drive bay; includes adapter for 2.5-inch hard drives)

Mouse

PS2, optical

USB, optical

USB, laser

Washable

Keyboards

PS/2

USB

USB, unbranded, Katydid

Smart card, CCID

Wireless keyboard, mouse, and dongle kit (for use in all countries except for Brazil)

Washable

14 Chapter 3 Illustrated parts catalog

Drives

Description

Hard drives and solid-state drives (SSDs)

2 TB, 7200 rpm, 3.5 inch

1 TB, hybrid SSD, 2.5-inch

1 TB, 10000 rpm

1 TB, 7200 rpm, 3.5 inch

500 GB, 10000 rpm

500 GB, 7200 rpm, 2.5 inch, self-encrypting (SED)

500 GB, hybrid SSD, 2.5 inch

500 GB, 7200 rpm, 3.5 inch

500 GB, 7200 rpm, 2.5 inch

500 GB, 5400 rpm, 2.5 inch

256 GB Solid-state Drive (SSD), self-encrypting (SED)

256 GB Solid-state Drive (SSD)

180 GB Solid-state Drive (SSD)

128 GB Solid-state Drive (SSD), self-encrypting (SED)

128 GB Solid-state Drive (SSD)

128 GB Solid-state Drive (SSD), M.2, PCIe

120 GB Solid-state Drive (SSD)

32 GB Solid-state drive (SSD), MLC

Optical drive

Blu-ray BD-RW SuperMulti XL Drive

DVD±RW drive

DVD-ROM drive

Drives 15

PCI boards

Description

(1) AMD Radeon HD8350 DH PCIe x16 graphics card, 1 GB

(2) Nvidia NVS310 PCIe x16 graphics card, 512 MB

Nvidia NVS315 PCIe x16 graphics card, 1 GB

AMD Radeon HD8490 DP PCIe x16 graphics card, 1 GB

AMD Radeon HD8470 PCIe x16 graphics card, 2 GB (for use only in the People’s Republic of China)

Nvidia GeForce GT630 DP PCIe x16 graphics card, 2 GB

(3) DisplayPort connector module

(4) Printer port, PCI card

(5) Serial port, PCI card

Intel PRO/1000 single port GbE NIC, includes bracket

16 Chapter 3 Illustrated parts catalog

4 Routine care, SATA drive guidelines, and

disassembly preparation

This chapter provides general service information for the computer. Adherence to the procedures and
precautions described in this chapter is essential for proper service.

CAUTION: When the computer is plugged into an AC power source, voltage is always applied to the system

board. You must disconnect the power cord from the power source before opening the computer to prevent
system board or component damage.

Electrostatic discharge information

A sudden discharge of static electricity from your finger or other conductor can destroy static-sensitive
devices or microcircuitry. Often the spark is neither felt nor heard, but damage occurs. An electronic device
exposed to electrostatic discharge (ESD) may not appear to be affected at all and can work perfectly
throughout a normal cycle. The device may function normally for a while, but it has been degraded in the
internal layers, reducing its life expectancy.

Networks built into many integrated circuits provide some protection, but in many cases, the discharge
contains enough power to alter device parameters or melt silicon junctions.

Generating static

The following table shows that:

●

Different activities generate different amounts of static electricity.

●

Static electricity increases as humidity decreases.

Relative Humidity

Event 55% 40% 10%

Walking across carpet

Walking across vinyl floor

Motions of bench worker

Removing DIPs from plastic tube

7,500 V

3,000 V

400 V

400 V

15,000 V

5,000 V

800 V

700 V

35,000 V

12,000 V

6,000 V

2,000 V

Removing DIPs from vinyl tray

Removing DIPs from Styrofoam

Removing bubble pack from PCB

Packing PCBs in foam-lined box

2,000 V

3,500 V

7,000 V

5,000 V

4,000 V

5,000 V

20,000 V

11,000 V

11,500 V

14,500 V

26,500 V

21,000 V

These are then multi-packaged inside plastic tubes, trays, or Styrofoam.

NOTE: 700 volts can degrade a product.

Electrostatic discharge information 17

Preventing electrostatic damage to equipment

Many electronic components are sensitive to ESD. Circuitry design and structure determine the degree of
sensitivity. The following packaging and grounding precautions are necessary to prevent damage to electric
components and accessories.

●

To avoid hand contact, transport products in static-safe containers such as tubes, bags, or boxes.

●

Protect all electrostatic parts and assemblies with conductive or approved containers or packaging.

●

Keep electrostatic sensitive parts in their containers until they arrive at static-free stations.

●

Place items on a grounded surface before removing them from their container.

●

Always be properly grounded when touching a sensitive component or assembly.

●

Avoid contact with pins, leads, or circuitry.

●

Place reusable electrostatic-sensitive parts from assemblies in protective packaging or conductive
foam.

Personal grounding methods and equipment

Use the following equipment to prevent static electricity damage to equipment:

●

Wrist straps are flexible straps with a maximum of one-megohm ± 10% resistance in the ground cords.
To provide proper ground, a strap must be worn snug against bare skin. The ground cord must be
connected and fit snugly into the banana plug connector on the grounding mat or workstation.

●

Heel straps/Toe straps/Boot straps can be used at standing workstations and are compatible with
most types of shoes or boots. On conductive floors or dissipative floor mats, use them on both feet with
a maximum of one-megohm ± 10% resistance between the operator and ground.

Static Shielding Protection Levels

Method Voltage

Antistatic plastic

Carbon-loaded plastic

Metallized laminate

1,500

7,500

15,000

Grounding the work area

To prevent static damage at the work area, use the following precautions:

●

Cover the work surface with approved static-dissipative material. Provide a wrist strap connected to the
work surface and properly grounded tools and equipment.

●

Use static-dissipative mats, foot straps, or air ionizers to give added protection.

●

Handle electrostatic sensitive components, parts, and assemblies by the case or PCB laminate. Handle
them only at static-free work areas.

●

Turn off power and input signals before inserting and removing connectors or test equipment.

●

Use fixtures made of static-safe materials when fixtures must directly contact dissipative surfaces.

●

Keep work area free of nonconductive materials such as ordinary plastic assembly aids and Styrofoam.

●

Use field service tools, such as cutters, screwdrivers, and vacuums, that are conductive.

18 Chapter 4 Routine care, SATA drive guidelines, and disassembly preparation

Recommended materials and equipment

Materials and equipment that are recommended for use in preventing static electricity include:

●

Antistatic tape

●

Antistatic smocks, aprons, or sleeve protectors

●

Conductive bins and other assembly or soldering aids

●

Conductive foam

●

Conductive tabletop workstations with ground cord of one-megohm +/- 10% resistance

●

Static-dissipative table or floor mats with hard tie to ground

●

Field service kits

●

Static awareness labels

●

Wrist straps and footwear straps providing one-megohm +/- 10% resistance

●

Material handling packages

●

Conductive plastic bags

●

Conductive plastic tubes

●

Conductive tote boxes

●

Opaque shielding bags

●

Transparent metallized shielding bags

●

Transparent shielding tubes

Operating guidelines

To prevent overheating and to help prolong the life of the computer:

●

Keep the computer away from excessive moisture, direct sunlight, and extremes of heat and cold.

●

Operate the computer on a sturdy, level surface. Leave a 10.2-cm (4-inch) clearance on all vented sides
of the computer and above the monitor to permit the required airflow.

●

Never restrict the airflow into the computer by blocking any vents or air intakes. Do not place the
keyboard, with the keyboard feet down, directly against the front of the desktop unit as this also
restricts airflow.

●

Occasionally clean the air vents on all vented sides of the computer. Lint, dust, and other foreign matter
can block the vents and limit the airflow. Be sure to unplug the computer before cleaning the air vents.

●

Never operate the computer with the cover or side panel removed.

●

Do not stack computers on top of each other or place computers so near each other that they are
subject to each other’s re-circulated or preheated air.

●

If the computer is to be operated within a separate enclosure, intake and exhaust ventilation must be
provided on the enclosure, and the same operating guidelines listed above will still apply.

●

Keep liquids away from the computer and keyboard.

Operating guidelines 19

●

Never cover the ventilation slots on the monitor with any type of material.

●

Install or enable power management functions of the operating system or other software, including
sleep states.

Routine care

General cleaning safety precautions

1. Never use solvents or flammable solutions to clean the computer.

2. Never immerse any parts in water or cleaning solutions; apply any liquids to a clean cloth and then use

the cloth on the component.

3. Always unplug the computer when cleaning with liquids or damp cloths.

4. Always unplug the computer before cleaning the keyboard, mouse, or air vents.

5. Disconnect the keyboard before cleaning it.

6. Wear safety glasses equipped with side shields when cleaning the keyboard.

Cleaning the Computer Case

Follow all safety precautions in General cleaning safety precautions on page 20 before cleaning the
computer.

To clean the computer case, follow the procedures described below:

●

To remove light stains or dirt, use plain water with a clean, lint-free cloth or swab.

●

For stronger stains, use a mild dishwashing liquid diluted with water. Rinse well by wiping it with a cloth
or swab dampened with clear water.

●

For stubborn stains, use isopropyl (rubbing) alcohol. No rinsing is needed as the alcohol will evaporate
quickly and not leave a residue.

●

After cleaning, always wipe the unit with a clean, lint-free cloth.

●

Occasionally clean the air vents on the computer. Lint and other foreign matter can block the vents and
limit the airflow.

Cleaning the keyboard

Follow all safety precautions in General cleaning safety precautions on page 20 before cleaning the
keyboard.

To clean the tops of the keys or the keyboard body, follow the procedures described in

Cleaning the

Computer Case on page 20.

When cleaning debris from under the keys, review all rules in

General cleaning safety precautions on page 20

before following these procedures:

CAUTION: Use safety glasses equipped with side shields before attempting to clean debris from under the

keys.

●

Visible debris underneath or between the keys may be removed by vacuuming or shaking.

●

Canned, pressurized air may be used to clean debris from under the keys. Caution should be used as too
much air pressure can dislodge lubricants applied under the wide keys.

20 Chapter 4 Routine care, SATA drive guidelines, and disassembly preparation