IBM XSERIES 255 TYPE 8685, Hardware Maintenance Manual And Troubleshooting Manual

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Note: See “System” on page 160 to determine which components should be replaced by a field service technician.
Monitor problems
Symptom FRU/action
Testing the monitor.
v See the information that comes with the monitor for adjusting and testing
instructions. (Some IBM monitors have their own self-tests.)
The screen is blank.
1. Verify that:
v
The server power cord is plugged into the server and a working electrical
outlet.
v
The monitor cables are connected properly.
v
The monitor is turned on and the Brightness and Contrast controls are
adjusted correctly.
v
If the servers are C2T chained together, verify that:
– The C2T chain cables are securely connected to the servers.
– The C2T breakout cable is connected properly.
– A server that is turned on is selected.
Important: In some memory configurations, the 3-3-3 beep code (see “Beep
symptoms” on page 127) might sound during POST followed by a blank display
screen. If this occurs and the Boot Fail Count feature in the Start Options of
the Configuration/Setup Utility program is set to Enabled (its default setting),
you must restart the server three times to force the system BIOS to reset the
CMOS values to the default configuration (memory connector or bank of
connectors enabled).
2. If you have verified these items and the screen remains blank, replace:
a. Monitor
b. Video adapter, if installed
c. System board
Only the cursor appears.
v
See “Undetermined problems” on page 157.
The monitor works when you
turn on the server but goes
blank when you start some
application programs.
1. Verify that:
v The application program is not setting a display mode higher than the
capability of the monitor.
v
The primary monitor cable is connected to the C2T device breakout cable.
v
You installed the necessary device drivers for the applications.
2. If you have verified these items and the screen remains blank, replace the
monitor.
The screen is wavy, unreadable,
rolling, distorted, or has screen
jitter.
1. If the monitor self-tests show the monitor is working properly, consider
the location of the monitor. Magnetic fields around other devices (such as
transformers, appliances, fluorescent lights, and other monitors) can cause
screen jitter or wavy, unreadable, rolling, or distorted screen images. If this
happens, turn off the monitor. (Moving a color monitor while it is turned on
might cause screen discoloration.) Then move the device and the monitor at
least 305 mm (12 in.) apart. Turn on the monitor.
Notes:
a. To prevent diskette drive read/write errors, be sure the distance between
monitors and diskette drives is at least 76 mm (3 in.).
b. Non-IBM monitor cables might cause unpredictable problems.
c. An enhanced monitor cable with additional shielding is available for the
9521 and 9527 monitors. For information about the enhanced monitor
cable, contact your IBM reseller or IBM marketing representative.
2. Video adapter, if installed.
3. System board.
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xSeries 255 Type 8685: Hardware Maintenance Manual and Troubleshooting Guide