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Rev D 8/12/12 Lab 3Under the Hood of My computer

IMPORTATANT SAFETY: Shut Power means remove power chord from outlet

Description: This lab should provide an introductory understanding of how the pieces of a computer fit and work together. The elements of a computer both hardware and software work in an extremely harmonious manner to accomplish amazing tasks and functions. We will explore and discover how this happens. When you have completed this lab you will be able to answer at a minimum the following questions in the Observations and Conclusions section of your final lab report.

Where do I connect the various Input/Output devices to my system unit? What are some of my computer’s internal devices and how do they tie together? What is the BIOS and its functions? What is the connection and difference between the BIOS and CMOS? Is the BIOS independent of the operating system(OS)? How do I detect visual problems without video feedback?

Procedure

1. Mark down computer provided vendor __________________model # _________________pen marked label # __________

2. Looking at back of your computer is a bunch of connectors. On figure 1 all of them are indicated with numbers. Fill in the numbers 1 to 3, 5, 7 to 8 and 10 to 13 on figure one next to the space of the connector description.

Figure 1. I/O Ports, Connectors, and Indicators

1 2 3 4 5 6

7 8 9 10 11 12 13

Lab 3(continued)

__ parallel __ serial connector (2)__ keyboard 9 diagnostic lights__ mouse __ USB connectors (2)4 link integrity __ audio line-out __ network adapter __ audio line-in 6 activity light __ microphone

___ serial connector

Computer Connector Reference:http://www.780tech.com/connectors/connectors.htm

 

 

RJ45(Networking)

Commonly associated with

Ethernet 10BaseT 

& 100Base TX

 

   

 

USB(Universal Serial

Bus)

Commonly associated

diverse devices including,

mouse, scanners,

printers, digital cameras etc

 

 

 

DB15 (2 rows)Female Connector

Game port/MIDI ALSO Network

version

 

Commonly associated with Joysticks, Joy

pads& Midi musical

instruments

Slightly different

version also associated with

Ethernet 10Base5

 

 

 

DB15 (3 Rows)

VGA / SVGA / XVGA Video

 

Commonly associated with

Video cards/ Display

adapters 

 

 

DB9 (Male)Serial port

Commonly associated with Serial devices

including Serial mouse & Modems

  DB25 (Male)Serial Port

Commonly associated with Serial devices including Serial

mouse & Modems

   

 

DB25 (Female)Parallel port

Also SCSI Version

Commonly associated with parallel devices

including printers,

Scanners & External drives

CENTRONICSPrinter Version SCSI Version is

wider

Commonly associated with

Printer interface

connectors & SCSI device connectors

 

 

 

DIN 5 (FEMALE)

AT Class Keyboard

Commonly associated with

Keyboard on AT Class

motherboards

3. Connect keyboard, mouse, monitor, and power cord to the computer. Remember any respectable computer must be able to do input and output. If not then it will only have brains and be considered a nerd. On the other hand someday it could become a very rich nerd.

4. Now turn power on to both the computer and monitor. Since we have no money you probably have a defective machine. (What do you expect? A dual core 3+ gig machine). Anyway the computer should provide some diagnostics to help out.. They include a sequence of 3 beeps, a possible error message (visible on screen only if display components not affected) and back panel diagnostic lights (figure 1 – 9). Some of the beeps will have a space of time between them. Mark down the beep sequence with the time spacing indicated, as for example 3-2-1.beep sequence _________________monitor display (error message?) _________________________diagnostic light colors (4 leds separated by commas starting top to bottom. eg Y,GR,Y,Y ) _______________________________________

Table 1. BIOS beep codesThe BIOS produces 3 sets of beeps, separated by short pauses.

Code Cause Action

1-1-2 Microprocessor register failure See Getting Help" for instructions on obtaining technical assistance.

1-1-3 NVRAM Run the System Board Devices tests in the Dell Diagnostics, if possible.

1-1-4 ROM BIOS checksum failure Run the System Board Devices tests in the Dell Diagnostics, if possible.

1-2-1 Programmable interval timer Run the System Board Devices tests in the Dell Diagnostics, if possible.

1-2-2 Direct memory access (DMA) initialization failure

Run the System Board Devices tests in the Dell Diagnostics, if possible.

1-2-3 DMA page register read/write failure

Run the System Board Devices tests in the Dell Diagnostics, if possible.

1-3 Video Memory Test failure Run the VESA/VGA Interface tests in theDell Diagnostics.

1-3-1 through 2-4-4

DIMMs not being properly identified or used

See "Computer Memory Problems."

3-1-1 Slave DMA register failure Run the System Board Devices tests in the Dell Diagnostics, if possible.

3-1-2 Master DMA register failure Run the System Board Devices tests in the Dell Diagnostics, if possible.

3-1-3 Master interrupt mask register failure

See "Getting Help" for instructions on obtaining technical assistance.

3-1-4 Slave interrupt mask register failure

See "Getting Help" for instructions on obtaining technical assistance.

3-2-2 Interrupt vector loading failure See "Getting Help" for instructions on obtaining technical assistance.

3-2-4 Keyboard ControllerTest failure

Run the Keyboard tests in the Dell Diagnostics. Otherwise, see "Getting Help" for instructions on obtaining technical assistance.

3-3-1 NVRAM power loss Run the System Board Devices tests in the Dell Diagnostics, if possible.

3-3-2 NVRAM configuration Run the System Board Devices tests in the Dell Diagnostics, if possible.

3-3-4 Video Memory Test failure Run the VESA/VGA Interface tests in theDell Diagnostics.

3-4-1 Screen initialization failure Run the VESA/VGA Interface tests in theDell Diagnostics.

3-4-2 Screen retrace failure Run the VESA/VGA Interface tests in theDell Diagnostics.

3-4-3 Search for video ROMFailure

Run the VESA/VGA Interface tests in theDell Diagnostics.

4-2-1 No time tick See "Getting Help" for instructions on obtaining technical assistance.

4-2-2 Shutdown failure See "Getting Help" for instructions on obtaining technical assistance.

4-2-3 Gate A20 failure See "Getting Help" for instructions on obtaining technical assistance.

4-2-4 Unexpected interrupt in protected mode

See "Getting Help" for instructions on obtaining technical assistance.

4-3-1 Memory failure above address 0FFFFh

Run the System Memory tests in the DellDiagnostics.

4-3-3 Timer-chip counter 2 failure See "Getting Help" for instructions on obtaining technical assistance.

4-3-4 Time-of-day clock stopped

See "Getting Help" for instructions on obtaining technical assistance.

4-4-1 Serial or parallel port test failure

Run the Serial Ports and the ParallelPorts tests in the Dell Diagnostics.

4-4-2 Failure to decompress code to shadowed memory

Run the System Board Devices tests in the Dell Diagnostics, if possible.

4-4-3 Math-coprocessor test failure Run the System Board Devices tests in the Dell Diagnostics, if possible.

4-4-4 Cache test failure Run the System Board Devices tests in the Dell Diagnostics if possible.

Diagnostic Lights

Light pattern

ProblemDescription

Suggested Resolution

off off off off

Normal off condition or possible pre- BIOS failure

Verify that the computer is plugged into a working outlet and that you have pressed the power button.

green yellow yellow yellow

Possible BIOSFailure

Contact Dell for technical assistance.

yellow green yellow yellow

Possible processor failure

Reseat the processor(s) and the terminator card (if present), and restart the computer to retest.

green green yellow yellow

Possible memory failure

Reseat all DIMMs and restart the computer to retest.

yellow yellow green yellow

Possible expansion card failure

Remove each expansion card individually, and restart the computer to retest.

Reinstall the expansion card(s) one at a time, and restart the computer to retest.

Move each expansion card one at a time to another PCI slot, and restart the computer to retest.

green yellow green yellow

Possible video card failure or bad on- board video

If you have a video card, reseat it and restart the computer to retest. If you have video integrated, you must replace the system board.

yellow green green yellow

Possible floppy or hard drive failure

Reseat all power and data cables, and restart the computer to retest.

green green green yellow

Possible USB failure Reseat all USB devices and cables, and restart the computer to retest.

yellow green green green

Other failure Contact Dell for technical assistance.

green green green green

Normal operating condition after POST

None.

5. In order to repair this problem review diagnostic indications noted and written above.

6. Did you find it?Note problem discovered ______________________________

7.Let us see what is causing it. Power down and open up computer using the two cover release buttons (1) indicated in figrure 2..

8.Check problem on the big circuit board called the mother board located as shown also in figure 2. (What happened to the father board? As Rodney Dangerfield says “we get no respect”).What’s wrong? _______________________________ Now fix the problem. We are not going to pay you for doing nothing. Oh we are not paying you guys anyway.

Figure 2 Computer Internals

1

5 1

6 2

7

3

8

4

1 cover release buttons (2) 5 CD/DVD drive

2 hard drive 6 3.5-inch floppy drive

3 internal speaker 7 system board

4 power supply 8 heat sink and blower assembly

Cable Co lors

Hard drive Blue

Floppy drive Black

CD/DVD drive Orange

USB Gray

ATA or IDE Green

Control panel Yellow

CD audio Blue

Computer audio Black

Lab 3(continued)

9. Now that you are inside the computer (not every on is invited to look inside ). From info provided figure out and fill in the numbers on the blank descriptions of the internal computer chassis items shown in figure 3.

Figure 3. System Board Components

1 2 3 4 5

306

292827

7

26

25 8

9

2410

11

12

23 22 21 20 19 18 17 16 15 14 13

ww

w .d

ell.c

om |

su

pp

ort

.del

l.co

m

Lab 3(continued)

Figure 3 Diagram Fill Ins

__ EIDE1 connector 16 audio line-out connector

__ front panel connector 17 12-volt microprocessor power connector

__ microprocessor and heat sink __ battery

__ internal speaker 19 keyboard (lower) and mouse (upper) connectors

__ floppy drive 20 diagnostic lights

6 suspend-to-RAM light 21 serial 2 connector

7 PCI riser (small mini-tower computer only) 22 parallel connector

8 standby power light 23 serial 1 connector

9 AGP connector __ EIDE2 connector

__ main power connector 25 memory module (DIMM) connectors

11 CD audio connector 26 fan connector

12 telephony connector (TAPI) __ PCI connectors

13 front audio connector __ network (upper) and USB connectors (2) (lower)

14 microphone connector 29 RTC reset jumper

15 audio line-in connector 30 password jumper

10. Read the internal power supply specs (figure 2 (4)). In this country the input power in watts is equal to 120 volts times amps drawn. The output is the DC watts. Answer the following:

maximum dc output in watts __________________maximum input current at 120 volts __________maximum input watts _____________efficiency of supply in % ___________What do you think of this efficiency?

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Lab 3(continued)

11. Working with an opened up computer turn power on. . Error beeps should not exist. If not go back to solving problem.Problem solved _______________________

12. If problem is solved system password is now probably being requested. We don’t have much but we are a proud department who protects their equipment. So there are two options. Get the password from the instructor (unlikely too mean; better chance with the technician) or bypass it.Since you are now in the computer world you do what is in fashion. We will bypass (disable it) and then have it changed.

13. Turn off power and carefully (we are always very polite) remove system jumper shown in figure 3(30). Do not lose jumper but place in a very safe spot. Your grade depends on this.

14. Power up again and see if system password has been disabled. Check off below when password requirement has been removed.No password required ____________

15. Well we can’t leave the system in this state. We need to introduce our own passwords for both the system and the BIOS setup. Power down and reinstall the system jumper (I told you not to lose it).Reinserted system jumper?_____________

16. We now want to reintroduce a new system password. To do this function we need to enter the BIOS setup. Of course to get to the BIOS you would key in something at the start up time. Try function key F2.

17. Power up again and key in the above found key(s) just at start up time to enter the BIOS setup. Select

a. System Security and enterb. System Password and enterc. Provide new password enter New system Password (of course we want to know)_______________

18. Entering the setup can also require a password. As before in 17, install a setup password.Setup password __________________

19. Now we need to test our change. Repower the system and call over your professor or the technician to check the workings of your new system and setup passwords. What do you think we don’t trust you guys changing the password correctly? Yes!Instructor or tech’s initials ____________________

Lab 3(continued)

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20. We are now going to get some info from our BIOS. Record the following settings.

Space for settings

System Time __________________________System Date __________________________Memory InfoInstalled System Memory ________________Memory Speed ________________________CPU InfoBus _________________________________PROCClock Speed __________________________Cache Size ___________________________Primary Drive 0 _______________________Primary Drive 1 _______________________Secondary Drive 0 _____________________Secondary Drive 1 _____________________

21. Do we see the physical drives that our BIOS indicate we have? (Remember the words of wisdom that seeing is believing and never trust a used car salesman or do I mean a used computer) Yes or No _________If no what drives are missing or extra? ____________

That’s all folks. The end

Author: H.S. Rev D Date 8/12/12

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