Can't Change IRQs in Windows 2000

Discussion in 'A+ Certification' started by RussS, Aug 9, 2003.

  1. RussS

    RussS Guest

    I don't think the IRQ sharing will be the problem. With W2K and XP IRQ
    sharing is the norm.

    Windows 2000 & XP take advantage of a relatively recent technology called
    ACPI (Advanced Configuration and Power Interface). This interface allows
    ACPI devices including your motherboard to share resources, listing some or
    all of these devices under the same IRQ, in your case IRQ9.

    Changing the settings to be controlled manually can be extremely complex and
    without knowing more about your set up and system, I wouldn't dream of
    giving you more specific advice.

    You say this is an older system - what are the specifications?
    RussS, Aug 9, 2003
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  2. RussS

    Alicia White Guest

    This is a "clean" install of Windows 2000 on an older system that seemed to
    proceed without a hitch: but it won't play DVDs! The thing locks up like a
    stone whenever I try it. I have this problem despite the fact that all the
    devices in the system are "working properly" with apparently no resource

    Oh, but my Win2K device manager lies like a dog! After viewing "Devices by
    Connection," I discover the awful truth: I have about a gazillion devices
    assigned to IRQ 9 and I can't change them to another IRQ despite having
    several free! Have a look:

    The PCI/AGP devices I have installed (no free slots):
    AGP video card
    DVD HW decoder
    sound card
    miroVIDEO video capture board
    USB 2.0 adapter

    IRQ assignments:
    0: system timer
    1: natural keyboard
    2: free
    3: free
    5: free
    4: COM1
    6: floppy controller
    7: free
    8: real time clock
    Microsoft ACPI-Compliant System
    Aureal Vortex audio
    Belkin USB 2.0 controller (high speed ethernet adapter is the only
    device connected to this)
    Cinemaster C 3.0 WDM main driver (DVD HW decoder)
    HCF 56K modem
    HW CineMaster C 3.0: DVD decoder
    Intel 82371AB/EB PCI to USB Universal Host Controller
    NEC PCI to USB Open Host Controller x 2
    Vortex Multifunction PCI Parent
    10: free
    11: free
    12: PS/2 mouse
    13: Numeric data processor
    14: Primary IDE
    15: Secondary IDE

    Now, needless to say, whenever I try to play a DVD the system locks up like
    a stone (audio, video, DVD HW decoding all using same IRQ!!!). Other than
    that, the system seems to work fine. I do get occassional lockups when
    surfing the internet, but they are few and far between. And, the system has
    no problem reading audio and data CDs or data DVDs. It is only when I try
    playing a DVD movie that it locks up hard..

    How can I change the IRQ assignments? The BIOS doesn't allow me to reserve
    any IRQs except those already not assigned (3, 5, 7, 10, 11). And, when I
    go to the device properties in the Device manageer, the option to manually
    assign resources is grayed out: VERY frustrating!

    Having a burning desire to watch "Stargate SG-1" DVDs on my PC, I was
    determined to find some way to resolve this resource problem. So, today, I
    finally found a Microsoft web page with a solution. Basically, the page
    says that Windows 2000 will not allow me to change IRQs (d'uh! figured that
    one out already!!). This is because the default HAL for my ACPI compliant
    system board will NOT allow me to change IRQs (... well, now at least I
    know WHY). Therefore, I need to reinstall Win2K and use the STANDARD PC HAL
    in order to restore my ability to make manual changes to IRQ assignments.

    See the MS page here:

    Has anyone else encountered this sort of problem? Does this solution work?

    I guess my big question is: do I need to make any corresponding changes to
    my BIOS settings?

    Currently, I believe that "PlugNPlay" OS is ENABLED. But, the MS tech
    article recommends disabling that. Are there other changes I should make to
    CMOS settings? If anyone can offer any advice or words of wisdom on this
    matter, I would be eternally grateful.

    Thanks! :)

    Alicia White
    Alicia White, Aug 9, 2003
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  3. RussS

    Alicia White Guest

    The system is a Dell XPS T500 (built Dec. 1999):
    768 MB RAM (originally had only 128MB, loaded it with Crucial RAM 2 years)
    PIII-500MHz CPU
    latest BIOS version is installed
    factory loaded with Win98se, now it has a fresh installation of Win2K Pro
    56K modem, AGP video, DVD decoder, DVD drive, CD-RW, USB 2.0 card,
    mirovideo DC20 video capture board, D-link router connected to d-link USB
    2.0 ethernet 10/100tx adapter, USB printer, USB ZIP drive, USB mouse and

    I don't think that IRQ sharing in itself is a problem: my system works fine
    most of the time. My system only locks up when I try playing a DVD movie.
    I can use DVD-ROM software without a problem.

    I have 5 separate devices related to DVD video playback which all use the
    same IRQ, so, I really think that is the source of the problem:
    Aureal Vortex audio
    Cinemaster C 3.0 WDM main driver
    HW CineMaster C 3.0: DVD decoder
    Vortex Multifunction PCI Parent
    Plus 3 non-DVD-related devices (3 devices related to USB 2.0 card)

    As I understand it, IRQ sharing will work without problems if you use
    complementary devices on the same IRQ that would not require the CPU's
    attention simultaneously (such as 2 NICs or 2 SCSI controllers). But, in my
    case, I have 5 devices that will probably try to use that IRQ simultaneously
    in order to play DVD video. So, that is why I believe that changing the IRQ
    assignments will enable me to watch my SG-1 dvds on my PC (or, so I hope).

    Am I wrong thinking the IRQ issue is the problem?


    See the MS article here:
    Alicia White, Aug 9, 2003
  4. RussS

    RussS Guest

    Hey Alicia

    I still don't think that is a problem. What is the DVD software you are
    RussS, Aug 9, 2003
  5. RussS

    Geoff Guest

    i think that feature of the bios just sets up the IRQ's for you and assumes
    your OS can't configure them itself, like windows 3.x (plug and play)

    settings plug n play to yes or no won't make much difference as win2k will
    change them to whatever it likes anyway, i generaly put no on that item

    setting it to standard HAL is a sucky fix really, but might fix it
    tryed updating the bios on the motherboard ?
    Geoff, Aug 12, 2003
  6. RussS

    Alicia White Guest

    The Dell ResourceCD only has drivers for Win98 and WinNT, it doesn't have
    anything for Win2K (I think Win2K was still in beta testing when my system
    was built in Dec. of '99).

    The Dell website does not appear to have a Win2K driver for this device
    available for download.

    On the ResourceCD, the User Manual for the decoder card has the following

    Q: DMA Enabled Checkbox Must be Checked

    A: If you experience problems with DVD playback, use Device Manager
    look at your CDROM devices (highlight the drive, then select Properties).
    Bring up the Settings tab. If the option "DMA" is present, verify that the
    checkbox for DMA is checked (enabled).

    I checked my DMA settings in the BIOS. Both the CD and DVD drive are set to
    DMA2 & Ultra DMA is disabled (all settings all grayed out so I can't change
    this). In Win2K, both the primary and secondary IDE controllers are set to
    "DMA if available."

    Alicia White, Aug 12, 2003
  7. RussS

    Alicia White Guest

    i do note that they are assigned to ICQ 9, which i don't like
    I looked in my BIOS: I have no such setting. I did set "Plug N Play OS" to
    NO. This didn't seem to change anything.

    So, should I reinstall Win2K and select STANDARD PC HAL as the MS technet
    article suggests? Would this accomplish the same thing as what you are

    See the MS article here:
    Ah, I would have preferred that, but I am out of PCI slots. And, I wanted
    to get a USB 2.0 card anyway so I can add an external drive later. BTW,
    this NIC adapter works great, I haven't had a problem with it.
    I wanted to be able to output video signal to my TV. You can't do that
    without a decoder card, at least not with the video card I have. I guess a
    lot of video cards these days have that capability, making a decoder card
    I have the latest drivers for the decoder card. Removing the card is not
    ideal solution: I want to be able to output video to my TV.


    Alicia White, Aug 12, 2003
  8. RussS

    spike Guest

    Cool! I will try that. I read the document and I am amazed that it could
    be that easy... hopefully it ain't too good to be true.

    I will report back with my results. Thanks, Razer! :)

    spike, Sep 1, 2003
  9. RussS

    Alicia White Guest

    Alright, I was ready to give up.

    I followed the instructions on that web site to change my PC from ACPI to
    STANDARD PC. After the somewhat nerve-wracking process of trying to locate
    and load the drivers for my legacy devices, I tried playing a DVD: it still
    didn't work!

    Instead of a hard lockup and reboot, I get an error in my DVD software
    window that says: "current display mode not suitable for dvd video." I use
    the DVD software made by Ravisent. When I tried the DVD software included
    with Win2K the system did a hard lock up and rebooted.

    I couldn't find satisfactory information on that error message so I was at a
    loss at how to troubleshoot the error.

    And, incidentally, going through the process of installing the STANDARD PC
    driver didn't resolve my inability to re-assign IRQs. The option is still
    grayed out in Device Manager, but the IRQ situation after changing to
    STANDARD PC is somewhat better than before:

    IRQ assignments:
    0: system timer
    1: PC/AT Enhanced PS/2 Keyboard (101/102-key)
    2: free
    3: free
    4: free
    5: free
    6: floppy controller
    7: Aureal Vortex 8830 Audio (WDM)
    Belkin USB 2.0 High Speed Host Controller
    HCF 56k PCI Modem #2
    Vortex Multifunction PCI Parent
    8: System CMOS/real time clock
    9: HW CineMaster C 3.0: DVD decoder
    Intel 82371AB/EB PCI to USB Universal Host Controller
    Vortex Multifunction PCI Parent
    10: Cinemaster C 3.0 WDM main driver (DVD HW decoder)
    NEC PCI to USB Open Host Controller
    11: NEC PCI to USB Open Host Controller
    12: Logitech PS/2 port mouse
    13: Numeric data processor
    14: Primary IDE Channel
    15: Secondary IDE Channel

    SIGH. I was ready to give up at this point.

    But, after writing the IRQs listed above, I compared them with my old list
    of IRQs (which I posted on this newsgroup before). I quickly realized that
    the name of the Video adapter was slightly different from before. So, I
    updated the driver to "NVIDIA RIVA TNT2/TNT Pro." I rebooted and FINALLY I
    can play DVDs! Once again, all is right in my dvd-loving world!

    Thanks, Razer! The link you gave me spared me the pain of having to
    reinstall Windows!

    (now I just have to see if my video capture board works again... but it's
    late, that can wait until later) <VBG>
    Alicia White, Sep 1, 2003
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