Checking the equipment, Troubleshooting irq assignment conflicts, Troubleshooting the video subsystem – Dell POWEREDGE 840 User Manual
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Troubleshooting Your System
Checking the Equipment
This section provides troubleshooting procedures for external devices attached to the system, such as the
monitor, keyboard, or mouse. Before you perform any of the procedures, see "Troubleshooting External
Connections."
Troubleshooting IRQ Assignment Conflicts
Most PCI devices can share an IRQ with another device, but they cannot use an IRQ simultaneously. To
avoid this type of conflict, see the documentation for each PCI device for specific IRQ requirements.
Table 4-2 lists the IRQ assignments.
Troubleshooting the Video Subsystem
Problem
•
Monitor is not working properly.
•
Video memory is faulty.
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
Remote access controller
IRQ6
Diskette drive controller
IRQ7
Available
IRQ8
Real-time clock
IRQ9
ACPI functions (used for power management)
IRQ10
Available
IRQ11
Available
IRQ12
PS/2 mouse port unless the mouse is disabled through the System Setup program
IRQ13
Math coprocessor
IRQ14
IDE optical drive controller
IRQ15
Available