IBM 7940, Problem Determination And Service Manual

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Monitor or video problems
Some IBM monitors have their own self-tests. If you suspect a problem with your
monitor, see the documentation that comes with the monitor for instructions for
testing and adjusting the monitor. If you cannot diagnose the problem, call for
service.
v Follow the suggested actions in the order in which they are listed in the Action column until the problem
is solved.
v
See Chapter 3, “Parts listing, Type 7940 and 7941 servers,” on page 19 to determine which components
are customer replaceable units (CRU) and which components are field replaceable units (FRU).
v
If an action step is preceded by “(Trained service technician only),” that step must be performed only by a
trained service technician.
Symptom Action
Testing the monitor.
1. Make sure that the monitor cables are firmly connected.
2. Try using a different monitor on the server, or try testing the monitor on a
different server.
3. If you are using a USB-connected monitor with an external USB hub,
disconnect the monitor from the hub and connect it directly to the server.
4. Run the diagnostic programs (see “Running the diagnostic programs” on page
101). If the monitor passes the diagnostic programs, the problem might be a
video device driver.
5. (Trained service technician only) Replace the system board
The screen is blank.
1. If you are using a USB-connected monitor with an external USB hub,
disconnect the monitor from the hub and connect it directly to the server.
2. Make sure that:
v
The server is turned on. If there is no power to the server, see “Power
problems” on page 95.
v
The monitor cables are connected correctly.
v The monitor is turned on and the brightness and contrast controls are
adjusted correctly.
v No beep codes sound when the server is turned on.
3. Make sure that the correct server is controlling the monitor, if applicable.
4. Make sure that damaged BIOS code is not affecting the video; see “Updating
the firmware” on page 15.
5. See “Solving undetermined problems” on page 121.
The monitor works when you
turn on the server, but the
screen goes blank when you
start some application
programs.
1. Make sure that:
v
The application program is not setting a display mode that is higher than the
capability of the monitor.
v You installed the necessary device drivers for the application.
2. Run video diagnostics (see “Running the diagnostic programs” on page 101).
v If the server passes the video diagnostics, the video is good; see “Solving
undetermined problems” on page 121.
v
(Trained service technician only) If the server fails the video diagnostics,
replace the system board.
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IBM System x3455 Type 7940 and 7941: Problem Determination and Service Guide