2.5.3Interrupt assignments

Standard Interrupt assignments

IRQ

Priority

Standard function

0

1

System Timer

1

2

Keyboard Controller

2

-

Programmable Interrupt

3*

11

Communications Port (COM2)

4*

12

Communications Port (COM1)

5*

13

--

6

14

Floppy Disk Controller

7*

15

--

8

3

System CMOS/Real Time Clock

9*

4

ACPI Mode when used

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.

2.5.4PCI Express x8 slot (x4 link)

The onboard PCI Express x8 slots provide one x4 link to CPU. The slots support VGA cards and various server class high performance add-on cards.

2.5.5PCI Express x16 slot (x16 link)

The onboard PCI Express x16 slot provides one x16 link to CPU. This slot supports VGA cards and various server class high performance add-on cards.

2.5.6PCI slots

The PCI slot supports cards such as a LAN card, USB card, and other cards that comply with PCI 2.3 specifications.

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Chapter 2: Hardware information