How to config IRQs?

Hi to everybody.

This is an issue I've miss for a long time and I thing it's time to learn. I know that some IRQ configs can make your computer slower or even unstable. Right now I'm using W98se but I never care about IRQ config (Windows is doing what it wants, oh my God!)

Well, there is a way to know the curent config? I've managed to learn it by using Config/System and going device by device, but that's horrible and slow!

Second, what will be the easy way to change it? There are some IRQs that can never be changed? What computer's components can share an IRQ? There is any rule?

In case it helps, right now I just have a NIC, HD, DVD and floppy, but I plan to add a USB webcam and a CD writer.

Any help would be really appreciated. Thanks in advance.


DIY: read, buy, test, learn, reward yourself!
11 answers Last reply
More about config irqs
  1. let the OS handle it. unless you're having a SERIOUS problem.

    <i>It's always the one thing you never suspected.</i>
  2. What exactly are you trying to accomplish, some of the IRQs are fixed IRQs, and sometimes you can trick Windows into reassigning some IRQs, but as I said what are you trying to accomplish.


    Details, Details, Its all in the Details, If you need help, Don't leave out the Details.
  3. Well, right now I'm not at home, so I can't check it. But I'll do it tonight and tell you exactly. Last time I was checking one by one through system config(slow method!), at least four "devices" where sharing the same IRQ (number 10 I think ...)

    Also, when I build up my computer I have a problem with VIA drivers (mobo is Epox 8KHA+). Curiously, through trial and error, I saw that I can only install 3 of the 4, because if not, things run terribly slow (I mean 10 minutes to open Windows!). Probably when everything was "activated" some IRQ was "over weighted".

    I try with another VIA drivers just to find out similar results. So now, that I want to add more peripherals to my computer I don't want to start hanging and doing the trial and error methodology (by luck, I use Ghost every time to male sure I have a copy of an operable config!)


    <b>DIY</b>: read, buy, test, learn, reward yourself! :cool:
  4. I only know a fast way to check your IRQs and things like that, you just have to run msinfo32 and then select hardware resources->IRQs. They are all listed there.

    In ancient times they had no statistics so they had to fall back on lies
  5. Some devices can share IRQs with no problems at all, the main troubles to avoid in Win98 and 98SE is your soundcard and videocard on the same IRQ, that definitely will eventually cause crashes. Ideally most Nvidia cards work better on IRQ 11, and soundcard on IRQ 5, Network Card on IRQ 10, some M/Bs can be a factor in either a successful or unsuccessful relocating of IRQs.

    Two things, List your IRQs and whats on each, and with the VIA drivers did you only install what was required for your OP SYS?


    Details, Details, Its all in the Details, If you need help, Don't leave out the Details.
  6. First of all thanks to all.

    Yesterday I checked all IRQ (I think I haven't missed any). The most "crowded" is in fact IRQ 10, with 3 USB and my NIC. Right now I'm not using any USB devide, but I plan to connect a Webcam any probably a ADSL modem.

    Tonight I will double check that I have write down all IRQs using your method <b>goloap</b>. I will also look my nvidia has IRQ 11 and soundcard IRQ 5.

    In case I needed, how can I change the IRQ? If I messed something really wrong there is a way to restore the "default Windows values"?

    About installing VIA drivers, I finally have 3 of the 4. I think I got the right one, you know, selecting W98se when I was going to download, and later I used the automatic installation.

    Finally, and just ot increase my knowledge, some IRQ are fixed? Some can never be used? And why?

    Thanks again to all.


    Still looking for a <b>good online retailer</b> in Spain :frown:
  7. List of IRQs

    Rt Click, My Computer, select properties

    Select Device Manager Tab

    Rt Click Computer, select properties

    Select: View Resources

    Select: Interrupt Request(IRQ)

    All IRQs will be listed in the window

    Write them down and post them


    Details, Details, Its all in the Details, If you need help, Don't leave out the Details.
  8. Ok, here you have the IRQs (there are more than I ever though!):

    0 - System chronometer
    1 - Keyboard
    2 - Programable interruptions controller
    3 - COM2
    4 - COM1
    5 - Something about IRQ ACPI for IRQ PCI management
    5 - Something about IRQ for PCI management
    5 - AC'97 (currently I'm using onboard sound)
    6 - Floppy
    7 - LPT1
    8 - System CMOS / real clock time
    9 - SCI IRQ used by ACPI bus.
    10 - Something about IRQ ACPI for IRQ PCI management (same description as nº 5)
    10 - VIA controller PCI - USB
    10 - VIA controller PCI - USB
    10 - VIA controller PCI - USB
    10 - My NIC
    11 - Something about IRQ ACPI for IRQ PCI management (same description as nº 5)
    11 - Something about IRQ for PCI management (same description as nº 5)
    11 - Nvidia GF3 (proud of it :smile: )
    12 - Mouse
    13 - Data numeric processor.
    14 - VIA bus Master PCI IDE controller
    14 - Primary IDE controller
    15 - VIA bus Master PCI IDE controller
    15 - Secondary IDE controller

    Sorry if some descriptions aren't accurate or don't match exactly with what you have. My Windows is the Spanish version, so I've translated as good as I can.

    Well, as you can see sound has IRQ 5 and GPU has IRQ 11. Should I have any problem if I install new hardware (Webcam + ADSL modem)? Any IRQ that doesn't seem right?

    I also would like to know if there is any general rule when working with IRQ that one should follow.

    Still looking for a <b>good online retailer</b> in Spain :frown:
  9. I don't see any problems, the controllers that are sharing IRQs with, your sound, video, and network cards, do not cause problems and will work perfectly fine just the way they are.

    Quote:
    I also would like to know if there is any general rule when working with IRQ that one should follow.

    YES! If everything is running OK, and your Video, Sound, and Network Cards are on separate IRQs, <b>Then leave well enough alone.</b>As Jlanka Already Said.


    Details, Details, Its all in the Details, If you need help, Don't leave out the Details.
  10. Ok, ok, I get it. Thanks for your help and patience.


    Still looking for a <b>good online retailer</b> in Spain :frown:
  11. If you feel you really need to free up another IRQ or two, disable your COM ports if you aren't using them. That will free up a couple IRQs without giving you any grief.

    <font color=red> If you design software that is fool-proof, only a fool will want to use it. </font color=red>
Ask a new question

Read More

Configuration Windows