User's Manual

Table 4-2.IRQAssignmentDefaults

Troubleshooting External Connections
Loose or improperly connected cables are the most likely source of problems for the system, monitor, and other peripherals (such as a printer, keyboard,
mouse, or other external device). Ensure that all external cables are securely attached to the external connectors on your system. See Front-Panel Features
and Indicators and Back-Panel Features and Indicators for the front- and back-panel connectors on your system.

Troubleshooting the Video Subsystem

Problem
l Monitor is not working properly.
l Video memory is faulty.

Action

1. Check the system and power connections to the monitor.

2. Swap the monitor with another working monitor to see if this resolves the problem.

3. Determine whether the system has an expansion card with a video output connector.
In this system configuration, the monitor cable should normally be connected to the connector on the expansion card, not to the system's integrated
video connector.
To verify that the monitor is connected to the correct video connector, turn off the system and wait for 1 minute, then connect the monitor to the other
video connector and turn the system on again.

4. Determine whether the system has monitors attached to both the front and rear video connectors.
The system supports only one monitor attached to either the front or rear video connector. When a monitor is connected to the front panel, the back-
panel video, keyboard, and mouse connectors are disabled.
If two monitors are attached to the system, disconnect one monitor. If the problem is not resolved, continue to the next step.

5. If possible, run the appropriate online diagnostic test. See Using Server Administrator Diagnostics.
If the tests run successfully, the problem is not related to video hardware.
If the tests fail, see Getting Help.


IRQ Line

Assignment
IRQ0
System timer
IRQ1
Keyboard controller
IRQ2
Interrupt controller 1 to enable IRQ8 through IRQ15
IRQ3
Serial port 2 (COM2 and COM4)
IRQ4
Serial port 1 (COM1 and COM3)
IRQ5
Remote access controller
IRQ6
Reserved
IRQ7
Reserved
IRQ8
Real-time clock
IRQ9
ACPI functions (used for power management)
IRQ10
Available
IRQ11
Available
IRQ12
Reserved
IRQ13
Math coprocessor
IRQ14
IDE CD drive controller
IRQ15
Available