Dell PowerEdge 850 Installation And Troubleshooting Manual page 103

each PCI device for specific IRQ requirements.
Table 4-2. IRQ Assignment Defaults
IRQ Line Assignment
IRQ0 System timer
IRQ1 Keyboard controller
IRQ2 Interrupt controller 1 to enable IRQ8 through IRQ15
IRQ3 Available
IRQ4 Serial port 1 (COM1 and COM3)
IRQ5 Available
IRQ6 Available
IRQ7 Available
IRQ8 Real-time clock
IRQ9 ACPI functions (used for power management)
IRQ10 Available
IRQ11 Available
IRQ12 PS/2 mouse port (available if the mouse is disabled through the System Setup program)
IRQ13 Math coprocessor
IRQ14 IDE optical drive controller (available if IDE CDROM controller is disabled through the System Setup program)
IRQ15 Reserved (available if IDE CDROM controller is disabled through the System Setup program)
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
panel connectors and Figure B-2 for the back-panel connectors on your system.
Troubleshooting the Video Subsystem
Problem
Monitor is not working properly.
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Video memory is faulty.
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Action
1. Check the system and power connections to the monitor.
2. 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, and PS/2 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.
3. Check the system and power connections to the monitor.
4. Run the appropriate online diagnostic test. See
If the tests run successfully, the problem is not related to video hardware.
If the tests fail, see "Getting
Troubleshooting the Keyboard
Problem
System message indicates a problem with the keyboard.
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Table 4-2 lists the IRQ assignments.
"Using Server Administrator
Help."
Diagnostics" in "Running System Diagnostics."
Figure B-1 for the front-