Author Topic: Troubleshooting the System Board  (Read 669 times)

La.kl

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Troubleshooting the System Board
« on: May 09, 2013, 01:37:48 PM »
The microprocessor, RAM modules, ROM BIOS, and CMOS battery are
typically replaceable units on the system board. If enough of the system is
running to perform tests on these units, you can replace them.
Problems with key system board components produce symptoms similar to
those described for a bad power supply. Both the microprocessor and the
ROM BIOS can be sources of such problems. You should check both by substitution
when dead system symptoms are encountered but the power supply
is good.
System Board Symptoms
Typical symptoms associated with system board hardware failures include the
following:
➤ The On/Off indicator lights are visible and the display is visible on the
monitor screen, but there is no disk drive action and no bootup occurs.
➤ The On/Off indicator lights are visible and the hard drive spins up, but
the system appears dead and there is no bootup.
➤ The system locks up during normal operation.
➤ The system produces a beep code with one, two, three, five, seven, or
nine beeps (BIOS dependent).
➤ The system produces a beep code of one long and three short beeps
(BIOS dependent).
➤ The system does not hold the current date and time.
➤ A DMA Error message displays, indicating a DMA controller failed page
register test.
➤ A CMOS Battery Low message displays, indicating failure of the CMOS
battery or the CMOS checksum test.
➤ A CMOS Checksum Failure message displays, indicating that the
CMOS battery is low or a CMOS checksum test failure.
➤ A 201 error code displays, indicating a RAM failure.
➤ A Parity Check error message displays, indicating a RAM error.
190 C. h.ap. te. r .3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Typical symptoms associated with system board CMOS setup failures
include the following:
➤ A CMOS Inoperational message displays, indicating failure of CMOS
shutdown register.
➤ A CMOS Memory Size Mismatch message displays, indicating a system
configuration and setup failure.
➤ A CMOS Time & Date Not Set message displays, indicating a system
configuration and setup failure.
Typical symptoms associated with system board I/O failures include the following:
➤ The speaker doesn’t work during operation. The rest of the system
works, but no sounds are produced through the speaker.
➤ The keyboard does not function after being replaced with a known-good unit.