This article describes how to force in a system Hardware
Abstraction Layer (HAL) during an upgrade or an installation of Microsoft
Windows XP. Note
The procedure to change from the Standard PC HAL to the Advanced
Configuration and Power Interface (ACPI) HAL differs in Windows XP from the
procedure that Microsoft Windows 2000 uses.
The HAL is computer code in Windows XP that makes it
possible for Windows XP to run on a variety of different computer types. The
HAL manipulates the computer hardware directly. During an upgrade or an
installation of Windows XP, you can “force in” a HAL by pressing the F5 key,
and then selecting from the available computer types.
Upgrade from Microsoft Windows 2000 to Windows XP
When you upgrade from Windows 2000 to Windows XP, the HAL is
preserved. For example, if the HAL on the Windows 2000-based computer is a
Standard PC HAL, that HAL is reinstalled when you upgrade to Windows XP.
In-place upgrade of Windows XP
When you perform an in-place upgrade, or a reinstallation of
Windows XP, if the Setup program detects that you have an unsupported HAL
installed for your computer type, and the Setup program determines that a HAL
that supports that computer type must be installed, it installs the correct
HAL. When this issue occurs, the HAL is changed from what was previously
Force in a system HAL
To prevent Windows XP from automatically determining the system
HAL during the upgrade or the installation of Windows XP, you can manually
force in a system HAL. To force in a system Hardware Abstraction Layer (HAL)
during an upgrade or installation of Windows XP, follow these steps:
- During the Text-mode phase of the Setup program, when you
receive the following message across the bottom of the screen, press F5:
Note If you press F7, the Standard PC HAL loads and the ACPI
compliance check is bypassed.
- You receive the following list of computer types. A brief
description of each HAL is included here:
- ACPI Multiprocessor PC
Applies to a multiple-processor ACPI computer.
- ACPI Uniprocessor PC
Applies to an ACPI multiple-processor board but with a
single processor installed.
- Advanced Configuration and Power Interface (ACPI) PC
Applies to a single processor motherboard with single
- Compaq SystemPro Multiprocessor or 100% Compatible
Applies to a Compaq SystemPro computer.
- MPS Uniprocessor PC
Applies to non-ACPI computers dual processor motherboard
with a single processor installed.
- MPS Multiprocessor PC
Applies to non-ACPI computers with a dual processor
- Standard PC
Applies to any Standard PC, non-ACPI, or non-MPS. The CPU
may be a 386, a 486, a Pentium, a Pentium II, or a Pentium III.
- Standard PC with C-Step i486
The screen displays only two computer types at a time. To scroll
up or down to view the complete list, use the arrow keys.
For additional information about
related topics, click the following article numbers to view the articles in the
Microsoft Knowledge Base:
Troubleshooting Windows 2000
Hardware Abstraction Layer issues
HAL options after Windows XP or Windows Server 2003 Setup