15
7. Install the necessary software driver for your expansion card.
2-5-2 Assigning IRQs For Expansion Card
Some expansion cards need an IRQ to operate. Generally, an IRQ must exclusively assign
to one use. In a standard design, there are 16 IRQs available but most of them are already
in use.
Standard Interrupt Assignments
IRQ Priority
Standard
function
0 1
System
Timer
1 2
Keyboard
Controller
2 N/A
Programmable
Interrupt
3 *
11
Communications Port (COM2)
4 *
12
Communications Port (COM1)
5 *
13
Sound Card (sometimes LPT2)
6
14
Floppy Disk Controller
7 *
15
Printer Port (LPT1)
8
3
System CMOS/Real Time Clock
9 *
4
ACPI Mode when enabled
10 *
5
IRQ Holder for PCI Steering
11 *
6
IRQ Holder for PCI Steering
12 *
7
PS/2 Compatible Mouse Port
13
8
Numeric Data Processor
14 *
9
Primary IDE Channel
15 *
10
Secondary IDE Channel
* These IRQs are usually available for ISA or PCI devices.
2-5-3 Interrupt Request Table For This Motherboard
Interrupt request are shared as shown the table below:
INT A INT B INT C INT D INT E INT F INT G INT H
Slot 1
√
Slot 2
√
Slot 3
√
Slot 4
√
Slot 5
√
Onboard VGA
Onboard USB 0
√
Onboard USB 1
√
AC97/MC97
√
