324 | Troubleshooting Your System
12 Remove the system-board assembly. See “Removing a System-Board
Assembly” on page 170.
13 Replace processor 1 with processor 2. See “Installing a Processor” on
page 178.
14 Repeat step 9 through step 11.
If you have tested both the processors and the problem persists, the
system board is faulty. See “Getting Help” on page 343.
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 4-1. Assignment Specific IRQ Requirements
IRQ Line
Assignment
IRQ0
8254 timer
IRQ1
Keyboard controller
IRQ2
Cascade for IRQ9
IRQ3
Serial port (COM2) or PCI_IRQ_POOL_DEFINITION
IRQ4
Serial port (COM1) or PCI_IRQ_POOL_DEFINITION
IRQ5
PCI_IRQ_POOL_DEFINITION
IRQ6
PCI_IRQ_POOL_DEFINITION
IRQ7
RESERVE
IRQ8
RTC
IRQ9
PCI_IRQ_POOL_DEFINITION
IRQ10
PCI_IRQ_POOL_DEFINITION
IRQ11
PCI_IRQ_POOL_DEFINITION
IRQ12
Mouse controller
IRQ13
Processor
IRQ14
Primary IDE controller
IRQ15
Secondary IDE controller
NOTE: PCI_IRQ_POOL_DEFINITION means BIOS code assign in runtime.