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Jesse,

The PCI bus shares IRQs as a matter of course.  It's not bad.  It's normal.  
x86 machines have this inherent design limitation (read "flaw" if you wish) 
that there are only 15 IRQs.  It goes way back to the 8086 days, back in the 
days when people said things like "who needs a computer faster than a 286", 
"640K is enough RAM for anyone", and "I'll never fill a 40 megabyte hard 
drive" (that last one was me, around 1989).  

That's hardly enough for modern computers with many devices on the bus.  So 
with PCI they added this extra layer of IRQ sharing to get around the limit.  
If you have old ISA cards, they can't share IRQs - if two of them share an 
IRQ, things don't work right.  That being said, nothings perfect.  While PCI 
devices _should_ share nicely, it's entirely possible one won't.  So to 
answer your first question, yes it could be a problem.  Unlikely in my 
personal experience, but certainly not impossible.

To answer your other question, about assigning IRQs, poke around your BIOS - 
that's what assigns IRQs, and generally there is some way to override the 
defaults.  Keeping in mind that you really only have a few IRQs to work with 
(since 14 and 15 are reserved for the IDE controller, 1 and 2 for the system, 
3 and 4 usually for COM ports, 7 for LPT, 6 and 8 for something I forget), 
that leaves you with 5 (though that's usually used for old Soundblaster 
backwards compatibility), 9, 10, and 11 (12, the one all your devices are on, 
is actually traditionally the PS2 port IRQ, so if you hardcode other devices 
to IRQs, pick one of the other ones.  I think 13 might be reserved too, or 
maybe it's just that it's an unlucky number  ;-)  ).  So if you have a lot of 
devices, you may just run out of IRQs before you run out of devices, and then 
you're back to sharing.  

That's all off the top of my head (the IRQ numbers) - Google can probably tell 
you more.

I notice one of the devices (per the log excerpts you gave) appears to be a 
video capture device (which you have commented on in the past on the list).  
Maybe one test you can do that is just as easy as changing BIOS settings is 
pull the card, and see if that helps.  That's my general solution to this 
sort of problem - pull stuff out until things start to work right.  If I get 
all the way down to just the RAM and processor, I know I'm in trouble.  ;-)

HTH

Ian
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