12
0 N/A
System
Timer
1 N/A
Keyboard
Controller
2 N/A
Programmable
Interrupt
3 *
8
Communications Port (COM2)
4 *
9
Communications Port (COM1)
5 *
6
Sound Card (sometimes LPT2)
6 *
11
Floppy Disk Controller
7 *
7
Printer Port (LPT1)
8 N/A
System
CMOS/Real Time Clock
9 *
10
ACPI Mode when enabled
10 *
3
IRQ Holder for PCI Steering
11 *
2
IRQ Holder for PCI Steering
12 *
4
PS/2 Compatible Mouse Port
13
N/A
Numeric Data Processor
14 *
5
Primary IDE Channel
15 *
1
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
√
Onboard VGA
√
Onboard USB
√
Onboard USB 1
√
Onboard USB 2
√
LAN
√
AC97/MC97
√
IMPORTANT!
If using PCI cards on shared slots, make sure that the drivers support “Shared
IRQ” or that the cards don’t need IRQ assignments. Conflicts will arise between
the two PCI groups that will make the system unstable or cards inoperable.
2-6 Connectors, Headers
2-6-1 Connectors
(1) Power Connector (20-pin block) : ATXPWR
