Knowledge Base

Drivers Fail to Load When I/O Address Is Above 0xFFF

Article ID: 162096

Article Last Modified on 11/1/2006

Microsoft Windows NT Workstation 3.51
Microsoft Windows NT Workstation 4.0 Developer Edition
Microsoft Windows NT Server 3.51
Microsoft Windows NT Server 4.0 Standard Edition

This article was previously published under Q162096

SYMPTOMS

When a driver is configured to use an input/output (I/O) base address greater than 0xFFF, the driver may fail to load when the system has a moon PCI-PCI bridge chipset.

CAUSE

The moon bridge has a read-only version of the I/O base and limit registers. Intel states that this means the bridge should get I/O ports ranging from 0 - 0xFFFF. Windows NT version 4.0 expects the I/O base range to be from 0 - 0xFFF.

STATUS

Microsoft has confirmed this to be a problem in Windows NT versions 3.51 and 4.0. This problem was corrected in the latest Microsoft Windows NT 4.0 U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K

Additional query words: prodnt

Keywords: kbbug kbnetwork KB162096