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                        ™
ThinkCentre 
Hardware Replacement Guide 
Types 8122, 8123, 8124 
Types 8131, 8137, 8138 
  
 
                                                                                                                                                                                                                                                                                                                                                                                                                 
                    
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                        ™ ThinkCentre  Hardware Replacement Guide  Types 8122, 8123, 8124  Types 8131, 8137, 8138                                                                                                                                                                                                                                                                                                                                                                                                                        
                    
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                          First Edition (April 2005)  © Copyright International Business Machines Corporation 2005. All rights reserved.  US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract  with IBM Corp.                                                                                                                                                                                                                                                                    
                    
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                          Contents  Removing and replacing the front bezel  . . . . .8  Overview  . . . . . . . . . . . . . .v  Replacing the power supply  . . . . . . . . .8  Safety information for replacing CRUs . . . . . .v  Replacing the system board assembly . . . . . .12  Safety information for replacing FRUs . . . . . .v  Replacing the microprocessor  . . . . . . . .19  Additional information resources  . . . . . . .v  Replacing a memory module  . . . . . . . .25  Tools required  . . . . . . . . . . . . .vi  Rep
                    
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                        iv Hardware Replacement Guide                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
                    
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                          Overview  This guide is intended to be used by customers who are replacing Customer  Replaceable Units (CRUs) as well as trained service personnel who are replacing  Field Replaceable Units (FRUs). In this guide CRUs and FRUs will often be  referred to as parts.  This guide does not include procedures for all parts. It is expected that cables,  switches, and certain mechanical parts can be replaced by trained service personnel  without the need for step-by-step procedures.  Note: Use only the 
                    
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                          Tools required  To replace some parts in your computer, you will need a flat-blade or Phillips  screwdriver. Additional tools might be needed for certain parts.  Handling static-sensitive devices  Static electricity, although harmless to you, can seriously damage computer  components.  When you are replacing a part, do not open the static-protective package  containing the new part until the defective part has been removed from the  computer and you are ready to install the new part.  When you
                    
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                          Chapter 1. Locations  This chapter provides illustrations to help locate the various connectors, controls  and components of the computer. To remove the computer cover, see “Removing  the computer cover” on page 5.  Locating components  The following illustration will help you locate the various components in your  computer.         1 Optical drive 6 System board  2 Memory modules 7 Lower drive cage (diskette drive and  hard disk drive)  3 Power supply 8 Internal speaker  4 PCI a
                    
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                          Locating controls and connectors on the front of the computer  This section shows the various external connectors on the computer to which you  can attach external devices.     1 3 9 4     1 IEEE 1394 connector (some 4 Microphone connector  models)  2 USB connector 5 Headphone connector  3 USB connector       2 Hardware Replacement Guide                                                                                                                                                     
                    
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                          Locating connectors on the rear of the computer  The following illustration shows the location of connectors on the rear of the  computer.         1 Power supply diagnostic 11 Ethernet connector  LEDs  2 Voltage selection switch 12 USB connectors (2)  3 Power connector 13 Standard keyboard connector  4 Audio line in connector 14 Standard mouse connector  5 Audio line out connector 15 PCI Express x16 adapter connector (some  models)  6 Microphone connector 16 PCI adapter
                    
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                          Identifying parts on the system board  The system board (sometimes called the planar or motherboard) is the main circuit  board in your computer. It provides basic computer functions and supports a  variety of devices.  The following illustration shows the locations of parts on the system board.         1 Internal speaker connector 12 PCI adapter connector  2 Memory connector 4 13 PCI adapter connector  3 Memory connector 3 14 Serial connector (COM 2)  4 Memory connector 2 15 P
                    
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                            Chapter 2. Replacing hardware    Attention:  Do not remove the computer cover or attempt any repair before reading the “Important  safety information” in the Quick Reference that was included with your computer or in the  Hardware Maintenance Manual (HMM) for the computer. To obtain copies of the Quick  Reference or HMM, go to http://www.ibm.com/pc/support.    Note: Use only the parts provided by IBM.  Removing the computer cover  Important       Turn off the computer and wait 3 to 5 minutes
                    
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                          6.   Some models have an optional hard disk drive mounting bracket 1 installed.  When this bracket is installed, access to some of the CRUs or FRUs inside the  chassis is restricted.  Note: There appears to be two drive bays in the bracket. However, due to  thermal restrictions, only the bay 2 at the rear of the chassis can be used to  install a hard disk drive.  See “Pivoting or removing the optional hard disk drive mounting bracket” on  page 7.      To replace the computer cover, see “Co
                    
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                          Pivoting or removing the optional hard disk drive mounting bracket  The optional hard disk drive mounting bracket can easily be pivoted upward or  removed if necessary to enable replacement of some CRUs and FRUs.  To pivot the optional hard disk drive bracket upward, pull outward at the bottom  of the bracket.      Note: You might have to disconnect the cables attached to the optional hard disk  drive.  If it is necessary to remove the optional hard disk drive mounting bracket,  disconnect the
                    
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                          Removing and replacing the front bezel  1.   Remove the computer cover. See “Removing the computer cover” on page 5.  2.   To release the front bezel from the chassis, press downward on the two plastic  tabs 1 and push the bezel outward as shown.      3.   To reinstall the bezel, align the plastic tabs 1 on the bottom of the bezel with  the corresponding holes in the chassis, then snap it into position at the bottom  and top of the chassis.  4.   Go to “Completing the installation” on page
                    
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                          2.   To access the 12 V power connector, remove the lower drive cage  thumb-screw and slide the lower drive cage toward the rear and out of the  bay. Place the drive cage out of your way without disconnecting the drive  signal cables.        3.   Disconnect the power supply cables 1 and 2 from the system board.        4.   Disconnect the power cable from each of the drives. Note the location of each  cable that is disconnected.  Chapter 2. Replacing hardware 9                              
                    
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                          5.   Remove the four screws that secure the power supply at the rear of the  chassis.        6.   Press inward on the metal retainer inside the chassis and slide the power  supply toward the front of the chassis and lift it out of the chassis as shown.        7.   Install the new power supply into the chassis so that the screw holes in the  power supply align with those in the chassis.  Note: Use only the screws provided with the new power supply.   8.   Install and tighten the four screws tha
                    
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                          9.   Reconnect power supply connectors 1 and 2 to the system board.      10.   Reinstall the lower drive cage and secure it with the thumb-screw.  11.   Reconnect a power supply connector to each of the drives.  12.   Go to “Completing the installation” on page 33.   Chapter 2. Replacing hardware 11                                                                                                                                                                                                  
                    
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                            Replacing the system board assembly    Attention:  Do not remove the computer cover or attempt any repair before reading the “Important  safety information” in the Quick Reference that was included with your computer or in the  Hardware Maintenance Manual (HMM) for the computer. To obtain copies of the Quick  Reference or HMM, go to http://www.ibm.com/pc/support.     1.   Turn off the computer and allow it to cool for one hour.   2.   Remove the computer cover. See “Removing the computer cov