Asus A7V-E Motherboard DIY Troubleshooting Guide - Page 25

3. H/W SETUP Expansion Cards 3. HARDWARE SETUP 3.7.2 Assigning IRQs for Expansion Cards Some expansion cards need an IRQ to operate. Generally, an IRQ must be exclusively assigned to one use. In a standard design, there are 16 IRQs available but most of them are already in use, leaving 6 IRQs free for expansion cards. If your motherboard has PCI audio onboard, an additional IRQ will be used. If your motherboard also has MIDI enabled, another IRQ will be used, leaving 4 IRQs free. The following table lists the default IRQ assignments for standard PC devices. Use this table when configuring your system and for resolving IRQ conflicts. Standard Interrupt Assignments IRQ Priority 0 1 1 2 2 N/A 3* 11 4* 12 5* 13 6 14 7* 15 8 3 9* 4 10* 5 11* 6 12* 7 13 8 14* 9 15* 10 Standard Function System Timer Keyboard Controller Programmable Interrupt Communications Port (COM2) Communications Port (COM1) Sound Card (sometimes LPT2) Floppy Disk Controller Printer Port (LPT1) System CMOS/Real Time Clock ACPI Mode when used IRQ Holder for PCI Steering IRQ Holder for PCI Steering PS/2 Compatible Mouse Port Numeric Data Processor Primary IDE Channel Secondary IDE Channel *These IRQs are usually available for PCI devices. Interrupt Request Table for this Motherboard PCI slot 1 PCI slot 2 PCI slot 3 PCI slot 4 PCI slot 5 PCI slot 6 AGP slot Onboard USB controller Onboard audio/SMBus INT-A shared - - - - - shared - - INT-B - used INT-C - - shared - - - - - shared INT-D - - - shared shared shared - shared - IMPORTANT: If using PCI cards on shared slots, ensure that the drivers support "Share IRQ" or that the cards do not need IRQ assignments. Conflicts may arise between the two PCI groups that will make the system unstable or cards inoperable. ASUS A7V-E User's Manual 25