Computer Assembly
Assembling computers is a large part of a technician's job. As a technician, you will need to work in a logical, methodical manner when working with computer components. As with any learned trade, computer assembly skills will improve dramatically with practice.
Sub-Topic:
Computer cases are produced in a variety of form factors. Form factors refer to the size and shape of the case.
Prepare the workspace before opening the computer case. There should be adequate lighting, good ventilation, and a comfortable room temperature. The workbench or table should be accessible from all sides. Avoid cluttering the surface of the workbench or table with tools and computer components. An antistatic mat on the table will help prevent physical and ESD damage to equipment. Small containers can be used to hold small screws and other parts as they are being removed.
There are different methods for opening cases. To learn how to open a particular computer case, consult the user manual or manufacturer's website. Most computer cases are opened in one of the following ways:
1. The computer case cover can be removed
as one piece.
2. The top and side panels of the case can be
removed.
3. The top of the case may need to be removed
before the side panel can be removed.
OPEN THE CASE
A technician may be required to replace or install a power supply. Most power supplies can only fit one way in the computer case. There are usually three or four screws that attach the power supply to the case. Power supplies have fans that can vibrate and loosen screws that are not secured. When installing a power supply, make sure that all of the screws are used and that they are properly tightened.
These are the power supply installation steps:
Optional Activity
Virtual Desktop: Power Supply
System requirements for the virtual desktop include a minimum of 512 MB RAM and Windows 2000 or Windows XP operating system.
Complete the power supply layer in the virtual desktop.
Lab: Install the Power Supply
Install a power supply in a computer case.
INSTALL THE POWER SUPPLY
This section details the steps to install components on the motherboard and then install the motherboard into the computer case.
Install a CPU and a heat sink/fan assembly.
Install the RAM.
Install the motherboard.
Install a CPU and a heat sink/fan Assembly
The CPU and the heat sink/fan assembly may be installed on the motherboard before the motherboard is placed in the computer case.
As shown in the video, a close-up view of the CPU and the motherboard. The CPU and motherboard are sensitive to electrostatic discharge. When handling a CPU and motherboard, make sure that you place them on a grounded antistatic mat. You should wear an antistatic wrist strap while working with these components.
CAUTION: When handling a CPU, do not touch the CPU contacts at any time.
The CPU is secured to the socket on the motherboard with a locking assembly. The CPU sockets today are ZIF sockets. You should be familiar with the locking assembly before attempting to install a CPU into the socket on the motherboard.
ATTACH THE COMPONETS TO THE MOTHERBOARD AND INSTALL THE MOTHERBOARD
Install the RAM
Like the CPU and the heat sink/fan assembly, RAM is installed in the motherboard before the motherboard is secured in the computer case. Before you install a memory module, consult the motherboard documentation or website of the manufacturer to ensure that the RAM is compatible with the motherboard.
RAM provides temporary data storage for the CPU while the computer is operating. RAM is volatile memory, which means that its contents are lost when the computer is shut down. Typically, more RAM will enhance the performance of your computer.
Follow these steps for RAM installation:
1. Align the notches on the RAM module to the keys
in the slot and press down until the side tabs click
into place.
2. Make sure that the side tabs have locked the RAM
module. Visually check for exposed contacts.
Repeat these steps for additional RAM modules.
Install the Motherboard
The motherboard is now ready to install in the computer case. Plastic and metal standoffs are used to mount the motherboard and to prevent it from touching the metal portions of the case. You should install only the standoffs that align with the holes in the motherboard. Installing any additional standoffs may prevent the motherboard from being seated properly in the computer case.
Follow these steps for motherboard installation:
Optional Activity
Virtual Desktop: Motherboard
System requirements for the virtual desktop include a minimum of 512 MB RAM and Windows 2000 or Windows XP operating system.
Complete the motherboard assembly in the virtual desktop motherboard layer.
Lab: Install the Motherboard
Install a CPU, a heat sink/fan assembly, and a RAM module on the motherboard.
Drives that are installed in internal bays are called internal drives. A hard disk drive (HDD) is an example of an internal drive.
Follow these steps for HDD installation:
1. Position the HDD so that it aligns with the 3.5-inch
drive bay.
2. Insert the HDD into the drive bay so that the screw
holes in the drive line up with the screw holes in the
case.
3. Secure the HDD to the case using the proper
screws.
Optional Activity
Virtual Desktop: Internal Drives
System requirements for the virtual desktop include a minimum of 512 MB RAM and Windows 2000 or Windows XP operating system. Complete the optical and floppy drive installation in the virtual desktop drives in external bays layer.
INSTALL INTERNAL DRIVES
Drives, such as optical drives and floppy drives, are installed in drive bays that are accessed from the front of the case. Optical drives and floppy drives store data on removable media. Drives in external bays allow access to the media without opening the case.
Install optical drive
An optical drive is a storage device that reads and writes information to CDs and DVDs. A Molex power connector provides the optical drive with power from the power supply. A PATA cable connects the optical drive to the motherboard.
Follow these steps for optical drive installation:
INSTALL DRIVES IN EXTERNAL BAYS
Install floppy drive
A floppy disk drive (FDD) is a storage device that reads and writes information to a floppy disk. A Berg power connector provides the FDD with power from the power supply. A floppy data cable connects the FDD to the motherboard.
A floppy disk drive fits into the 3.5-inch bay on the front of the computer case.
Follow these steps for FDD installation:
Optional Activity
Virtual Desktop: Drives in External Bays
System requirements for the virtual desktop include a minimum of 512 MB RAM and Windows 2000 or Windows XP operating system.
Complete the optical and floppy drive installation in the virtual desktop drives in external bays layer.
Lab: Install the Drives
Install the hard disk drive, the optical drive, and the floppy drive.
Adapter cards are installed to add functionality to a computer. Adapter cards must be compatible with the expansion slot. This section focuses on the installation of three types of adapter cards:
Install NIC or Wireless NIC
A NIC or a wireless NIC enables a computer to connect to a network or a wireless network. NICs use PCI and PCIe expansion slots on the motherboard. Some wireless NICs are installed externally with a USB connector.
Follow these steps for NIC installation:
INSTALL ADAPTER CARDS
Install video adapter cards
A video adapter card is the interface between a computer and a display monitor. An upgraded video adapter card can provide better graphic capabilities for games and graphic programs. Video adapter cards use PCI, AGP, and PCIe expansion slots on the motherboard.
Follow these steps for video adapter card installation:
Optional Activity
Virtual Desktop: Adapter Cards �System requirements for the virtual desktop include a minimum of 512 MB RAM and Windows 2000 or Windows XP operating system.
.
Complete the NIC, wireless NIC, and video adapter card installation in the virtual desktop adapter card layer.
Lab: Install Adapter Cards
Install a NIC, a wireless NIC, and a video adapter card
Connect the power cables
Power cables are used to distribute electricity from the power supply to the motherboard and other components Data cables transmit data between the motherboard and storage devices, such as hard drives. Additional cables connect the buttons and link lights on the front of the computer case to the motherboard
Motherboard Power Connections�
Just like other components, motherboards require power to operate. The Advanced Technology Extended (ATX) main power connector will have either 20 or 24 pins. The power supply may also have a 4-pin or 6-pin Auxiliary (AUX) power connector that connects to the motherboard. A 20-pin connector will work in a motherboard with a 24-pin socket.
Follow these steps for motherboard power cable installation:
.
CONNECT ALL INTERNAL CABLES
SATA Power Connectors�
SATA power connectors use a 15-pin connector. SATA power connectors are used to connect to hard disk drives, optical drives, or any devices that have a SATA power socket.
Molex Power Connectors�Hard disk drives and optical drives that do not have SATA power sockets use a Molex power connector.
CAUTION: Do not use a Molex connector and a SATA power connector on the same drive at the same time.
Follow these steps for power connector installation:
4. Connect the 3-pin fan power connector into the
appropriate fan header on the motherboard,
according to the motherboard manual.
5. Plug the additional cables from the case into the
appropriate connectors according to the motherboard
manual.
video 1
CONNECT ALL INTERNAL CABLES
video 2
video 3
Connect the data cable�
Drives connect to the motherboard using data cables. The drive being connected determines the type of data cable used. The types of data cables are PATA, SATA, and floppy disk.
PATA Data Cables
The PATA cable is sometimes called a ribbon cable because it is wide and flat. The PATA cable can have either 40 or 80 conductors. A PATA cable usually has three 40-pin connectors. One connector at the end of the cable connects to the motherboard. The other two connectors connect to drives. If multiple hard drives are installed, the master drive connects to the end connector. The slave drive connects to the middle connector.
A stripe on the data cable denotes the location of pin 1. Plug the PATA cable into the drive with the pin 1 indicator on the cable aligned to the pin 1 indicator on the drive connector. The pin 1 indicator on the drive connector is usually closest
to the powerconnector on the drive. Many motherboards have two PATA drive controllers, providing support for a maximum of four PATA drives
SATA Data Cables
The SATA data cable has a 7-pin connector. One end of the cable is connected to the motherboard. The other end is connected to any drive that has a SATA data connector.
Floppy Data Cables
The floppy drive data cable has a 34-pin connector. Like the PATA data cable, the floppy drive data cable has a stripe to denote the location of pin 1.
A floppy drive cable usually has three 34-pin connectors. One connector at the end of the cable connects to the motherboard. The other two connectors connect to drives. If multiple floppy drives are installed, the A: drive connects to the end connector. The B: drive connects to the middle connector.
RE-ATTACH THE SIDE PANELS AND CONNECT EXTERNAL CABLES TO THE COMPUTERS
Now that all the internal components have been installed and connected to the motherboard and power supply, the side panels are re-attached to the computer case. The next step is to connect the cables for all computer peripherals and the power cable.
Re-attach the side panels to the case
Most computer cases have two panels, one on each side. Some compute r cases have one three-sided cover that slides down over the case frame.
When the cover is in place, make sure that it is secured at all screw locations. Some computer cases use screws that are inserted with a screwdriver. Other cases have knob-type screws that can be tightened by hand.
If you are unsure about how to remove or replace the computer case, refer to the documentation or
.
website of the manufacturer for more information.
CAUTION: Handle case parts with care. Some computer case covers have sharp or jagged edges
Connect external cables to the computer
After the case panels have been re-attached, connect the cables to the back of the computer. Here are some common external cable connections:
When attaching cables, ensure that they are connected to the correct locations on the computer. For example, some mouse and keyboard cables use the same type of PS/2 connector.
CAUTION: When attaching cables, never force a connection.
NOTE: Plug in the power cable after you have connected all other cables.
Follow these steps for external cable installation:
When the computer is booted, the basic input/output system (BIOS) performs a check on all of the internal components. This check is called a power-on self test (POST).
Identify beep codes
POST checks to see that all of the hardware in the computer is operating correctly.
If a device is malfunctioning, an error or a beep code alerts the technician that there is a problem. Typically, a single beep denotes that the computer is functioning properly. If there is a hardware problem, the computer might emit a series of beeps. Each BIOS manufacturer uses different codes to indicate hardware problems.
BOOT THE COMPUTER FOR THE FIRST TIME
Describe the Bios setup
The BIOS contains a setup program used to configure settings for hardware devices. The configuration data is saved to a special memory chip called a Complementary Metal Oxide Semiconductor (CMOS), as shown in Figure 1. CMOS is maintained by the battery in the computer. If this battery dies, all BIOS setup configuration data will be lost. If this occurs, replace the battery and reconfigure the BIOS settings.
To enter the BIOS setup program, you must press the proper key or key sequence during POST. Most computers use the DEL key. Your computer might use another key or combination of keys.
Video shows an example of a BIOS setup program. Here are some common BIOS setup menu options:
Lab:Boot the Computer�Boot the computer for the first time, explore the BIOS setup program, and change the boot order sequence
Summary:
This chapter detailed the steps used to assemble a computer and to boot the system for the first time. These are some important points to remember: