WinNT x86 MPS HAL Can Fail To Map System Relative IRQs

Article translations Article translations
Article ID: 182540 - View products that this article applies to.
This article was previously published under Q182540
This article has been archived. It is offered "as is" and will no longer be updated.
Expand all | Collapse all


Under very specific circumstances, Windows NT may fail to assign a system- relative Interrupt Request Level (IRQL) to a Peripheral Component Interconnect (PCI) device.

A driver first calls HalAssignSlotResources to retrieve the bus-relative IRQL for the PCI device. When the driver calls HalGetInterruptVector to map the bus-relative IRQL, the call may fail.


This problem is caused when a multiprocessor hardware-abstraction layer (HAL) is used on a specific PCI configuration. For any non-zero bus, if a PCI device is at Device #0 and it is the only PCI device on that bus, the interrupt assignment fails. If there is more than one PCI device on the bus, this problem does not occur.

This problem has occurred on systems with PCI Accelerated Graphics Port (AGP) video devices because they are typically the only devices on the bus and they are not on bus zero. Also, systems with multiple PCI buses might have this problem.


To resolve this problem, obtain the latest service pack for Windows NT 4.0 or Windows NT Server 4.0, Terminal Server Edition. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
152734 How to Obtain the Latest Windows NT 4.0 Service Pack


Microsoft has confirmed that this is a problem in Windows NT 4.0 and Windows NT Server 4.0, Terminal Server Edition. This problem was first corrected in Windows NT 4.0 Service Pack 4.0 and Windows NT Server 4.0, Terminal Server Edition Service Pack 4.


Hardware developers writing device drivers under multiple PCI bus systems may experience this problem. If your PCI device drivers are configured as described above and you experience this failure when calling HalGetInterruptVector, contact Microsoft Technical Support to obtain a hotfix.


Article ID: 182540 - Last Review: October 7, 2013 - Revision: 2.2
  • Microsoft Windows NT Server 4.0, Terminal Server Edition
  • Microsoft Windows NT Server 4.0 Standard Edition
  • Microsoft Windows NT Workstation 4.0 Developer Edition
  • Microsoft Windows NT Server 4.0 Enterprise Edition
kbnosurvey kbarchive kbhotfixserver kbqfe kbbug kbfix KB182540

Contact us for more help

Contact us for more help
Connect with Answer Desk for expert help.
Get more support from