Are you using the floppy port?...If not turn it off...it is redundant...right?
 
Now as irq assignments go, I believe some are reserved for OS, and pnp holders for OS to put or assign when this is set in some bios to none..You gain some control over managing of those attributes...You must try to see that is clearly understood first...some , and some of your wall will go away you put, saying it does not have or does not allow, or cannot do, or It just cannot do...Are all the things you need to solve for...Not me, I just said it can be one, And I have done it...That is , I did it that way and other ways, None solve any issues I was having...So, it might work for you, but I doubt it will solve any issues!...or it puts ,in the way of you doing any management of or for when PNP OS is used ..and you put too much in, or of wanting put... closed systems ID dictates to the OS a set list of default requirements be placed when installing of OS and some id info must be gleened by the OS to see what it has to put to make the mb bootable, and have some features working properly , as detected as enabled,... or full system setup by Dell or other as self contained units bought as already setup, and chipsets and bus/slot routings...sometimes are hard to break and remake into something they were not designed for...as some are known to be problematic..with third party devices....Firewire is a Non PC device of legacy...It might work, but apple is the holder of the legal rights?..I know MS may have worked on with...But, USB is MS OSes Baby...and it will cause problems...for other third party devices...So you move to that protocol....It is in the best interests of MS to push its own development, and push its own ports....So Good luck with that.
 
it is like Explorer and Netscape wars...what happened to netscape ?...gone?...wow, and I thought they won the trial wars, and MS Lost the default fighting...and now edge is still tied to OS with Bing!.
 
 
Any hoot...You see where I see Hay only feeds the horse so long.,,until the horse forgets the pasture is poisoned with...lies and liars!...So some fine soul made Elephants that never forget!....lol
 
Win 10 at its first conception...and the way it was pushed on some...Ruined any TB, or firewire and some new systems, and audio went buggy more so with streaming and internet, and audio device issues and plug ins went also into some sort of spin in hold mode, until MS got things proper...Not sure even now it is completely solved for the damages...and a lot of devices did not work because of...and then they sent down the candy crush games and such...all free!...to tie up even more, and put more things on or upon without permissions, and set default setups to their own reset by!
 
Now some say, it was just to remove and reinstall the drivers, to solve for?...not all worked as said to do, and game mode is put to solve, and the download issues of those games to solve, plus reset all the tweaks and such...circles ontop of circles....always fixing the PC.
 
Win 7 on my motherboard today, has no internet services, or device working proper, so it says in event viewer and logs made..and the icon is covered by a circle and line of red over it on the task bar...
 
Oh yes, some found a way to fix this...But it does not work here!.
 
Internet is working...but it says, and logs every so often a log file saying this service cannot run, because the device is not working properly....when it is.
and it says it is off...when it is not.
 
And so...MS sucks at a lot of things.
 
Just saying, it may be written do this to fix that , try that, fiddle this in, and fiddle this out...update, upgrade, and pay more for more of...the same old same old.
 
Now when you get the snitzel of the best of PC parts and put in the time and effort to make a real fine build....Consider multiple paths of ...multi boot, and multi os platforms to run that with RND of OSes for PC..Do not just use MS os...as it is seemingly Buggy for a reason!.
 
Then you can make the machine that best services you.
Not the other way around?...well tables must turn eventually!.
 
Now if after all these fine people chimming in...and I cannot give you any solutions...with links or not...nor get you or the bios of which I have no control over...to do, what it cannot do...who can you think...we can read your manual and solve what you cannot solve, with that machine...not in my hands?..or seeing is believing?...I cannot fix...if you have it...You have to find the way...I can not point you in the right direction...I only offer you good advice.
 
turn off what is not necessary...or being used....and you free up the sharing!...and that is all you can do, so you say...Do it...and it is done.
 
or..get a better machine...with a better bios and OS...or use XP..turn off redundancies, put slots and device/irq, and such to make exclusive irq proper, then install the OS...no PNP os set if so can be?..Not sure about that ?...and get the drivers sorted manually.
 
That is how I do it now...Because, if you do not do it liken this...MS OS will put defaults in..and hold them even if you put never drivers...those defaults will be hidden it put, and in some cases they revert to those things, instead of, or they do not allow the new driver be used..because MS believes it has installed the best drivers already!.
 
Now that, is a sure twisting being witnessed also in windows 10.
and some cannot install new drivers...and some things just disappear when installed....wow...
 
So if you are  having issues with XP...I feel your pain...But I can only say...IRQ management is iffy at best@ if you can put up with the crap of MS..and say I like the way it works for me....Read up on the how to do they put for you to go in circles.
 
I know...I am the two thousand year old Elephant with long hair now and a tan!
 
 
Just saying...lol.
 
 
 
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The only remaining possibility I can think of at the moment is turning everything on in the BIOS (LPT, COM, LAN, Etc) and have the firewire card also installed at that time.  Then re-install the OS to see if maybe it decides to move things around differently IRQ wise when it sees a fully populated machine, rather than trying to hide everything at install.    That's about the only other idea I have left at this point.    Oh...and maybe installing the chipset drivers at OS install instead of afterwards.  Not quite sure how to do that however given the chipset download is in post-OS-installation format.
 
One strange observation I noticed is that if I install the OS with no graphic driver then the OS uses the default VGA driver and maps it to IRQ11.  But if I install the proper graphic driver the OS moves it to IRQ 16.  It's like the machine is possessed by a demon that insists on moving everything in the system onto the same IRQ16.  Everything that isn't a legacy device is on IRQ16 - EXCEPT for the USB bus/ports - only 1 out of the 6 USB ports is on IRQ16.   
 
I don't get it...never seen anything quite like this before.....   
 
Sonic

So, I just tried lowering my latency to see what would happen.  With RME's awesome WDM/Kernel drivers I am able to get down to 10ms latency.   If I attempt one setting lower (5ms) it sounds all static-filled.  10ms is plenty fine for me though in terms of being able to input "real-time" MIDI drum beats just for the sake of programming drum tracks.   I also noticed however the 'denormalization' issue that used to be present with Pentium 4 CPU's is still there with the Pentium Dual Core (E5700) to an extent.  That's unfortunate.   I'm also sometimes encountering a louder than normal "pop" when playback stops, which I've narrowed down as coming from DFH Superior Synth tracks.  Otherwise, overall things seems to be functioning pretty well thus far.

Sonic

Good to hear it's functioning well. I think you have a very old fashioned view of how IRQs are supposed to work. For instance, PCIe doesn't even have any hardware interrupt lines. The fact that IRQ16 even comes into play should tell you that you're working with virtual IRQs - old-fashioned "hardware" IRQs run 0 to 15.
Although I don't know exactly how advanced XP is in handling this stuff, it seems it's handling your stuff just fine.

Understood, but clearly there's something relevant going on.  Because if IRQ's didn't matter then why have them??  And why are the USB ports broken up among various IRQ's but nothing else? Why not just put them all on IRQ16 as well??   Clearly there is a trigger & processing, whatever that may be.  If it isn't an IRQ in the traditional sense then it's something similar, and all these "devices" on the same IRQ cannot be good is what I still maintain.  If it wasn't an issue then the system could simply put EVERYTHING on the same IRQ, or even use none at all, right?

Because the USB ports are legacy hardware? Exactly what you said before. Still don't understand why you are insisting this is a problem when your system is working fine.

I agree that dedicated IRQ requests are not relevant to PCIe, and are for legacy ISA based systems.  Since APIC systems are the norm today, which have been standard for many years, a virtual IRQ is to be expected.
 
Google APIC and there are some interesting discussions on the topic.