IRQ

M4at0t,

Thank you for using the Dell Community Forum.
WindowsXP and 2000 use IRQ sharing and that leaves the IRQ assignments totally
up to the operating system. To get around this you can try installing the
device in other PCI slots. If the device you are installing is XP or 2000 compliant,
it should have no problems with the shared IRQs.
IRQ reservation in the bios is for legacy devices that need to run in a DOS based
environment. Once you boot up to WinXP or 2000, those reservations no longer matter as the operating system takes control.

M4a2t0r,

Disabling ACPI is suppose to keep Windows from assigning IRQs.
The problem comes in on how the process was done.
Microsoft recommends that you reinstall XP or 2000 as an upgrade or fresh install.
If you disabled ACPI after the operating system had been installed, it simply
stops the detection of any new devices and keeps the operating system from
assigning IRQs. So...to disable ACPI properly you have to reinstall the operating system.
Here is information I have gathered on this process.
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A General Description of IRQ Sharing in Windows XP
The information in this article applies to:
Microsoft Windows XP Home Edition
Microsoft Windows XP Professional
This article was previously published under Q314068
For a Microsoft Windows 2000 version of this article, see 252420.

NOTE: This article is for informational use only. It does not contain any troubleshooting information. If you are searching for troubleshooting information that is not mentioned in this article, search the Microsoft Knowledge Base again by using keywords that are listed in the following Microsoft Knowledge Base article:
242450 How to Query the Microsoft Knowledge Base Using Keywords

SUMMARY:
This article offers a general description of how interrupt request (IRQ) sharing is managed in Windows XP. The description includes an explanation of why many of the devices on your computer seem to use the same IRQ and why Windows XP does not include resource rebalancing.

MORE INFORMATION:
In Windows, peripheral component interconnect (PCI) devices can share IRQs. In accord with the Plug and Play capability that is defined by the PCI specification, adapters are configured by the computer BIOS and are then examined by the operating system and changed if necessary. It is normal behavior for PCI devices to have IRQs shared among them, especially on Advanced Configuration and Power Interface (ACPI) computers that have Windows ACPI support enabled.

In Windows XP, Device Manager may list some or all of the devices on your ACPI motherboard as using the same IRQ (IRQ 9). (To view the list of resources, click either Resources by type or Resources by connection on the View menu). No option is available to change the IRQ setting. Windows takes advantage of the ACPI features of the motherboard, including advanced PCI sharing. The PCI bus uses IRQ 9 for IRQ steering. This feature lets you add more devices without generating IRQ conflicts.

Note that Windows XP cannot rebalance resources in the same way that Microsoft Windows 98 does. After PCI resources are set, they generally cannot be changed. If you change to an invalid IRQ setting or I/O range for the bus that a device is on, Windows XP cannot compensate by rebalancing the resource that was assigned to that bus.

Windows XP does not have this ability because of the more complex hardware schemas that Windows XP is designed to support. Windows 98 does not have to support IOAPICs, multiple root PCI buses, multiple-processor systems, and so on. When you are dealing with these hardware schemas, rebalancing becomes risky and therefore is not implemented in Windows XP except for very specific scenarios. However, PCI devices are required to be able to share IRQs. In general, the ability to share IRQs does not prevent any hardware from working.

The Plug and Play operating system settings in the computer BIOS do not generally affect how Windows XP handles the hardware. However, Microsoft recommends that you set the Plug and Play operating system setting to No or Disabled in the computer BIOS. For information about viewing or modifying the computer BIOS settings, consult the computer documentation or contact the computer manufacturer.

Manually assigning IRQs to PCI slots in the system BIOS as a troubleshooting method may work on some non-ACPI systems that use a standard PC hardware abstraction layer (HAL), but these settings are ignored by Plug and Play in Windows if ACPI support is enabled. If you need to manually assign IRQ addresses through the BIOS to a device on an ACPI motherboard, you must reinstall Windows to force the installation to use a Standard PC HAL. For additional information, click the article number below to view the article in the Microsoft Knowledge Base:
299340 How to Force a Hardware Abstraction Layer During an Upgrade or New Installation of Windows XP
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How to Disable IRQ Sharing for 16-Bit PC Cards That Do Not Support ISA-to-PCI Routed Interrupts
The information in this article applies to:
Microsoft Windows XP Home Edition
Microsoft Windows XP Professional
This article was previously published under Q279256
IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:
256986 Description of the Microsoft Windows Registry

SYMPTOMS:
The R2 PC Card does not start, and you see the following error message in Device Manager:
This device is either not present, not working properly, or does not have all the drivers installed. (Code 10)
Try upgrading the device drivers for this device.

CAUSE:
This behavior occurs because some R2 PC Cards do not support interrupt request (IRQ) resource sharing. In Windows XP, 16-bit PC Card (PCMCIA) PCI readers can use R2 PC Cards (the 16-bit ISA type) without requiring an ISA runner paddle to obtain ISA interrupts.

RESOLUTION:
WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

To resolve this behavior, disable the ISA-to-PCI routing feature to allow these PC Cards to function in laptop computers:
Start Registry Editor (Regedit.exe).
Locate the following key in the registry:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\PCMCIA\Parameters

On the Edit menu, click Add Value, and then add the following registry value:
Value Name: DisableIsaToPciRouting
Data Type: REG_DWORD
Value: 1

Quit Registry Editor.
This procedure disables PCI routing for 16-bit PC Cards. With this feature, you can successfully install 16-bit PC Cards on computers that are low on ISA interrupts by using a shared-PCI interrupt.
Note: If you disable this feature, the device could potentially display an error code 12 (not enough free resources) in Device Manager if there is not a suitable free interrupt for the card to use. You may have to disable an unused device or port to make an IRQ available for the card.
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Unable to Change Resource Settings in Windows XP Device Manager
The information in this article applies to:
Microsoft Windows XP Home Edition
Microsoft Windows XP Professional
Microsoft Windows XP 64-Bit Edition
This article was previously published under Q315278
For a Microsoft Windows 2000 version of this article, see 269491.

SYMPTOMS:
On a computer that is running the Advanced Configuration and Power Interface (ACPI) Hardware Abstraction Layer (HAL), you are not able to change a resource setting for a device in Device Manager.
If you modify the resource settings in the BIOS, the changes do not register.

CAUSE:
This behavior occurs because the ACPI HAL controls resource assignments in Windows XP and does not permit user intervention.

STATUS:
This behavior is by design.

MORE INFORMATION
Microsoft does not recommend that you change the HAL that is installed during the Windows XP Setup process. When you change from the ACPI HAL to the Standard PC HAL, you must reinstall the operating system, and ACPI functionality is lost.
In some rare instances, you may need to have control over a resource assignment. You can manually configure resources in Windows only if you are using Standard PC HAL, and even then you may not be able to configure some devices. The device must support manually setting of resources.
For additional information, click the article number below to view the article in the Microsoft Knowledge Base:
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How to Troubleshoot Windows 2000 Hardware Abstraction Layer Issues
Microsoft Knowledge Base Article - 237556
The information in this article applies to:
Microsoft Windows 2000 Server
Microsoft Windows 2000 Advanced Server
Microsoft Windows 2000 Professional
Microsoft Windows XP HOME
Microsoft Windows XP PRO

The article includes information on how to disable the ACPI features of Windows.
URL location is:
http://support.microsoft.com/default.aspx?scid=kb;EN-US;237556
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thx for the detailed response. when I disabled ACPI it was during the XP setup. It turns out it was a driver problem, It was a real pain to install, I had to download and install the latest driver then I managed to find just the media center and its working finally.

M4a2t0t,

Glad that you got it working.