15
2-5 Expansion Cards
2-5-1 Procedure For Expansion Card Installation
1. Read the documentation for your expansion card and make any necessary hardware or
software setting for your expansion card such as jumpers.
2. Remove your computer’s cover and the bracket plate on the slot you intend to use.
3. Align the card’s connectors and press firmly.
4. Secure the card on the slot with the screen you remove above.
5. Replace the computer system’s cover.
6. Set up the BIOS if necessary.
7. Install the necessary software driver for your expansion card.
2-5-2 Assigning IRQs for Expansion Card
Some expansion cards need to set up the IRQ to operate. An IRQ must be assigned
exclusively to single interface use only. There are 16 IRQs available but most of them are
already being used.
Standard Interrupt Assignments
IRQ Priority Standard function
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.