How do I see/change the IRQ(L) of my device?

In the BIOS

This is probably the best place to check to change your IRQs.

On Windows

Open the device manager, right click a device and click Properties. Then go to the Resources tab.

This allows you to see/change the IRQ (Levels):

alt text

On Linux

Open up a shell and execute:

cat /proc/interrupts

This for example, gives:

           CPU0       CPU1       CPU2       CPU3
  0:        187          0          0          0   IO-APIC-edge      timer
  1:      39922          0          0          0   IO-APIC-edge      i8042
  7:          0          0          0          0   IO-APIC-edge      parport0
  8:          4          0          0          0   IO-APIC-edge      rtc
  9:          1          0          0          0   IO-APIC-fasteoi   acpi
 12:     846774          0          0          0   IO-APIC-edge      i8042
 14:     105048          0          0          0   IO-APIC-edge      libata
 15:          0          0          0          0   IO-APIC-edge      libata
 16:    1069722          0          0          0   IO-APIC-fasteoi   libata, uhci_hcd:usb4, nvidia
 17:     105382          0          0          0   IO-APIC-fasteoi   eth0
 18:      83040          0          0          0   IO-APIC-fasteoi   uhci_hcd:usb2, libata
 19:          0          0          0          0   IO-APIC-fasteoi   uhci_hcd:usb1, ehci_hcd:usb5
 20:     474168          0          0          0   IO-APIC-fasteoi   uhci_hcd:usb3, ohci1394, ra0
 21:      10117          0          0          0   IO-APIC-fasteoi   bttv0
 22:     594327          0          0          0   IO-APIC-fasteoi   HDA Intel
NMI:          0          0          0          0
LOC:    1754492    1545836    2085855    1878596
ERR:          0
MIS:          0

Tamara Wijsman

Posted 2011-01-22T21:39:33.493

Reputation: 54 163

very nice! I'm impressed! - will upvote when I get more votes – studiohack – 2011-01-22T21:52:17.607

-1. On windows that shows the IRQ associated with the device, not the IRQL that the OP asked for. I don't know enough about linux to be sure but I'm guessing it also shows the IRQ not IRQL. – pipTheGeek – 2011-02-01T19:46:35.907

No, the IRQ is a number indicating which interupt line the device is connected to. The IRQL is a number maintained by the OS which controls which interupts are allowed to interupt which other interupts. There is more information here http://ext2fsd.sourceforge.net/documents/irql.htm

– pipTheGeek – 2011-02-01T21:11:43.553

Adjusted, see @pipTheGeek link for an in-depth explanation. :-) – Tamara Wijsman – 2011-02-01T21:21:41.933