DebuggingIRQProblems
Debugging IRQ Problems
What is an IRQ
An IRQ is a way that hardware talks to the Operating System, in this case Ubuntu. It does this by sending an interupt request, hence IRQ. Sometimes these interupts get mixed up and the message does not get through, eg two devices use the same IRQ then one is never going to work. Modern devices typically resolve this themselves, but sometimes we need help.
A BIOS is a basic Input Output System. This starts your computer for you and allows you to configure devices before the computer is booted, seen press esc to configure when you first switch on you computer. If you have no experience with this don't touch these settings, get an expert.
How do I know there is a problem
The following are some symptoms which may indicate an IRQ-related problem:
- Hardware devices being detected, but not functional (sound, network, etc.)
- Problems using two hardware devices at the same time, or only when devices are connected at the same time
- System hangs
What do I do
If you think you may be experiencing such a problem, try these steps in order:
Boot the system with the noapic boot parameter
Boot the system with the pci=routeirq
Boot the system with the pci=noacpi boot parameter
Boot the system with the acpi=off boot parameter
Each of these options disables a feature of Ubuntu. If this fails you might try:
If that fails
1) If you have a Bios conflict also ensure you check your bios to see if some of the items can be turned off temporarily (serial ports etc).
2) Try changing the order of the cards in your pc. I've seen it where due to bios issues cards work in certain slots and not in others.
If you are experiencing system panics or hangs, follow the instructions at DebuggingSystemCrash