Solved

Changing IRQ settings in XP

Posted on 2003-11-05
2
12,703 Views
Last Modified: 2012-06-21
I can't change the IRQ settings in windows xp. They are greyed out, any ideas on how to activate manual settings??

thanks
/Kristofer
0
Comment
Question by:kristofer
  • 2
2 Comments
 
LVL 57

Accepted Solution

by:
Pete Long earned 50 total points
ID: 9686517
Hi kristofer,
Knowledge Base  

A General Description of IRQ Sharing in Windows XPPSS ID Number: 314068

Article Last Modified on 10/4/2002


--------------------------------------------------------------------------------
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

Keywords: kbHardware kbinfo kbPlugPlay KB314068
Technology: kbWinXPHome kbWinXPHomeSearch kbWinXPPro kbWinXPProSearch kbWinXPSearch



--------------------------------------------------------------------------------

Send feedback to Microsoft

© 2003 Microsoft Corporation. All rights reserved.


Cheers!
0
 
LVL 57

Expert Comment

by:Pete Long
ID: 9789285
ThanQ
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Disclosure: Use this tutorial only when no other options helps to get Windows XP running without any problems and you don't want to format the drive. The back up of the data is the responsible of the user, however there is a description of how t…
Can you find a fax from a vendor you saved a decade ago in seconds? Have you ever cursed your PC under your breath during an audit because you couldn’t find the requested statement or driver history?  If you answered no to the first question or yes …
This demo shows you how to set up the containerized NetScaler CPX with NetScaler Management and Analytics System in a non-routable Mesos/Marathon environment for use with Micro-Services applications.
This video demonstrates how to create an example email signature rule for a department in a company using CodeTwo Exchange Rules. The signature will be inserted beneath users' latest emails in conversations and will be displayed in users' Sent Items…

929 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

13 Experts available now in Live!

Get 1:1 Help Now