Comment 18 for bug 276445

Just for a quick test....
As I see your wifi0 is sharing the interrupt with usb, firewire and sound card..
21: 935070 930591 IO-APIC-fasteoi uhci_hcd:usb4, ohci1394, wifi0, HDA Intel

So try to disable from your BIOS the usb, firewire and sound card if possible.
Then boot again and check the behavior!

As you see in my interrupts below, with the new motherboard there is one interrupt for each device so there is no conflict...

I will also mention that the previous motherboard with the problem, had an intel G31 chipset and the new one has an nvidia nForce 630i chipset on it.

# cat /proc/interrupts
           CPU0 CPU1
  0: 1203 0 IO-APIC-edge timer
  1: 8 0 IO-APIC-edge i8042
  4: 9 0 IO-APIC-edge
  6: 3 0 IO-APIC-edge floppy
  7: 1 0 IO-APIC-edge parport0
  8: 395131632 0 IO-APIC-edge rtc
  9: 0 0 IO-APIC-fasteoi acpi
 14: 2287253 0 IO-APIC-edge libata
 15: 0 0 IO-APIC-edge libata
 16: 0 0 IO-APIC-fasteoi ehci_hcd:usb1
 17: 0 0 IO-APIC-fasteoi ohci_hcd:usb2
 19: 5533159 0 IO-APIC-fasteoi eth1
 21: 49688720 0 IO-APIC-fasteoi wifi0
 22: 45243350 0 IO-APIC-fasteoi wifi1
 23: 45394020 0 IO-APIC-fasteoi wifi2
219: 25591033 0 PCI-MSI-edge eth0
220: 0 0 PCI-MSI-edge ahci
NMI: 0 0 Non-maskable interrupts
LOC: 22864422 20017440 Local timer interrupts
RES: 254929 17108105 Rescheduling interrupts
CAL: 43693 169442 function call interrupts
TLB: 257536 285735 TLB shootdowns
TRM: 0 0 Thermal event interrupts
SPU: 0 0 Spurious interrupts
ERR: 1
MIS: 0