ReBoot Hardware

Module 19

BIOS/CMOS/Flash Memory Chip

• BIOS or BIOS ROM = Basic Input/Output System– Lowest level software in the computer– Provides access to system hardware for the computer

operating system

• BIOS settings are stored on CMOS or Flash Memory Chips.– Older Computer have CMOS chips = complementary metal oxide semiconductor

– Newer computers have Flash Memory Chips, which can be updated with BIOS revisions.

BIOS’ first task: POST

• POST = Power-On Self Test– Identifies, analyzes, and sets up the

components in the computer: keyboard, video, etc.

– Some errors are fatal – system stops dead. (Example: no memory)

– Single beep means system OK, and the boot continues.

POST Error Messages

.– Errors are reported with speaker beeps or printed

code messages.– Beeps and coded messages can be interpreted – see

motherboard manual, manufacturer’s website, or– go to PC Hell at http://

www.pchell.com/hardware/beepcodes.shtml – Or, go to a more extensive list of both beeps and

messages at http://bioscentral.com/

BIOS Setup• How to get in?

– Press a key or combination of keys before the operating systems starts to load.

• What keys?– Key combinations are usually shown on boot screen.

• Screen disappears too fast to read?– Press the pause key. This stops the boot processes and freezes

the screen so you can read it. (Press enter to continue the boot.)

• No keys displayed?– Check your motherboard or computer manual, or check the

manufacturer’s Internet site. – Some information is at

http://www.michaelstevenstech.com/bios_manufacturer.htm

BIOS Setup

• Why?– Error code needs attention. (hard drive, memory, etc.)– You need information about BIOS settings or

computer hardware.– You want to make changes in settings, such as

passwords.

Warning: Making changes to BIOS settings can have adverse effects on the way a computer performs. Use caution when performing BIOS modifications.

BIOS Passwords

Security Passwords - security passwords to control access to the system at boot time and/or when entering the BIOS setup program. Supervisor Password supersedes User Password.

• Forgot Your Passwords!!!!– There is hope…For procedures, go to

http://www.pcguide.com/ts/x/comp/mbsys/cmosLostPassword-c.html

Forgot your Password!!!

• Recommendations: from http://www.pcguide.com/ • If you haven't already, and if you can live without the

machine for a day or so, wait and try to remember the password. This is the best solution, if you can remember it. :^)

• If your system has an AMI BIOS, try the default password, which is either "AMI" or "ami". This will not usually work, but is worth a try.

• If you cannot get into the BIOS program, your only remaining option is to try to clear the CMOS memory that holds BIOS settings. Included in this memory is the password, so this will let you get back into the PC. See here for instructions on erasing the CMOS memory.

EDO, SDRAM, RDRAM, SRAM, DDR SDRAM, DDR2 SDRAM, non-pariety, configuration, pins, sizes??

Memory – things to think about?• How much memory do I need? • How much memory will my system

recognize? • What kind of memory is compatible with

my system? • How many sockets are open and how

should I fill them? All the same? descending order? Fill which first?

• Quality, Prices, ???

Order Carefully!

• Some machines have specific memory requirements.– Check computer or motherboard manuals.– Check manufacturer websites.– Many suppliers offer a configuration search page to

help you avoid mistakes. Some Examples.• http://www.crucial.com/ http://

www.shop.kingston.com/default.asp?bannersource=comju • http://www.pny.com/configurator/ • http://www.comtread.com/

Before you install…• Place your computer's power switch in the off position and

disconnect the AC power cord.

• Follow the instructions in your owner's manual that describe how to locate your computer's memory expansion sockets.

• Before touching any electronic components or opening the package containing your new module(s), make sure you first touch an unpainted, grounded metal object to discharge any static electricity you may have stored on your body or clothing.

• Handle your new module(s) carefully; do not flex or bend the module(s). Always grasp the module by its edges.

The above from http://www.kingston.com/tools/umg/umg07.asp

Installing DIMM Memory

• Spread the ejector tabs on each end of the socket apart.

• Align the notches on the bottom edge of the Dimm with the tabs in bottom of the socket.

• Slide the card into the grooves on each end of the socket, and carefully push the card straight down until the ejector tabs pop up and catch the ends of the card.

• Check to see if the Dimm is correctly seated and tight.

Installing Older Style Simm Memory

• Note that one side of the card has a cutout on one lower edge. One end of the socket will fit this cutout. Both ends of the socket have spring tabs that will hold the Simm upright and in place. Also you must match the notch in the bottom of the Simm with a tab in the socket.

• Align the memory card with the socket at about a 45 degree angle.

• Seat the bottom of the Simm into the socket, snap the top gently upright, so the ends are held by the snap springs.

Cards?

• PCI, ISA, AGP,

• Video, Sound, SCSI controller, Network?

Card Install & Uninstall

• To install, remove the slot cover, usually by removing a screw at the top.

• Align the card with the socket and push it gently and firmly until it is seated.

• Reinstall the screw to secure the card.

• To uninstall, remove the screw, and pull the card straight up out of the socket.

• Put a spare slot cover in the space where you removed the card.

Hard Drives

• Is it really dead?– No longer recognized by BIOS? Check to see

if settings have been changed.– Check that ribbon cable and power cable are

correctly installed.– Check Jumpers for correct master or slave

setting.– Dreaded Click of the Dead Hard Drive.. RIP

Troubleshooting chart, from

http://www.fonerbooks.com/ide_hd.htm

Find the Hard Drive

• Place your computer's power switch in the off position and disconnect the AC power cord.

• Remove the case cover. On a tower you may need to remove both sides.

• The IDE hard drive should be in one of the 3.5 inch drive bays. It will usually be held in the bay by 2 screws on each side.

• The drive will be connected to the motherboard by a ribbon cable, and connected to the power supply by a standard 4 wire power connector.

IDE Ribbon (Data) Cable, and Power Cable

• These cables are connected to the back of the drive.

• Remember the orientation of these cables, using the red wire on the power cable and the red strip on the ribbon as guides.

Configuration Jumpers

• If there are two devices connected to the IDE cable, one must be designated as master, or primary device, and the other must be slave, or secondary device.

• Configuration jumpers on the back of the drive assign this role.

Removal• Gently remove the ribbon data

cable from the rear of the drive by pulling on the plastic end piece, not the ribbon.

• Note that the ribbon cable is connected on the other end into the motherboard.

• There may be two drives connected to the ribbon cable.

• The red edge of the ribbon cable is connected it to pin 1.

• Do the same with the power cable. Note the orientation of the power cable.

• Remove the 4 screws and slide the drive out of its bay.

• Don’t Drop The Drive. It’s Fragile!

Installation

• Set the jumper configuration.

• Follow the preceding steps in reverse to reinstall the drive.

• Check the drive ribbon cable, power connector, and all other connections that you may have touched to make sure they are correctly installed and tight.

Sources of Information and Images

• http://www.fonerbooks.com/pcrepair.htm

• http://www.bioscentral.com/ • http://en.wikipedia.org/wiki/BIOS • http://www.pcguide.com/index.htm • http://www.bios-drivers.com/• http://www.michaelstevenstech.co

m/bios_manufacturer.htm• http://

www.pchell.com/hardware/beepcodes.shtml

• http://www.pchell.com/• http://www.youcanbuildapc.com/

images/pcislots.jpg • http://www.mid.muohio.edu/

computer/techtips/images/cards3.jpg

• http://www.computermemoryupgrade.net/types-of-computer-memory-common-uses.html

• http://www.kingston.com/tools/umg/umg07.asp

• http://www.fonerbooks.com/ide_hd.htm

• http://www.pcguide.com/proc/physinst/hdd.htm

• http://www.hitachigst.com/hdd/support/images/cablemt.jpg

• http://www.wizri.com/wdold.gif • http://www.ontrack.com/jumpervie

wer/

• http://www.pcworld.com/hereshow/graphics/47370-1906p194-5b.jpg