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HAL (Hardware Abstraction Layer)

The term "computer type" and "HAL" have the same meaning, and may be interchanged.

• HAL Descriptions for Specific Computers
• What is the HAL?
• Why Knowing the HAL is Important
• How to Determine Your Computer Type
• Possible values for the HAL
• Universal Imaging Utility by Binary Research International reduces HAL dependencies.
• Computer Tips Index

HAL Descriptions for Specific Computers

*As reported via Device Manager > Computer

Notes:

Dell OptiPlex GX110:

I checked three GX110's and they all display a different HAL between Windows 2000 Professional and Windows 2000 Advanaced Server, as listed in the chart above. They have multiple bootable partitions. If I ever have the time, I'll attempt to figure out why there is a difference of HAL's on the same computer.

What is HAL?

Short for hardware abstraction layer, programming in an operating system that functions as an interface between a system’s hardware and software, providing a consistent hardware platform on which to run applications. When a HAL is employed, applications do not access hardware directly but access the abstract layer provided by the HAL. Like APIs, HALs allow applications to be device-independent because they abstract information from such systems as caches, I/O buses and interrupts use this data to give the software a way to interact with the specific requirements of the hardware on which it is running.
Source: Webopedia.com

A hardware abstraction layer is a layer between the physical hardware of a computer and the software that runs on that computer. The function is to hide differences in hardware and therefore provide a consistent platform to run applications on.

The best example of an HAL can be found in the AS/400 architecture. The implementation of the LIC or Lincensed Internal Code, was so successful that software written on the predecessor, the S/38, runs without modifications on an AS/400. The underlying hardware has changed dramatically, at least 3 different types of processors have been in use.

BSD, Linux and the Windows NT based operating systems, also have an HAL. These operating systems have different subsystems for particular functions e.g. sound and vision.
Source: Wikipedia, the free encyclopedia.

Why Knowing the HAL is Important?

When cloning/imaging different computer systems, the target system needs to have the same HAL Description as the source system. Don't waste your time if the HAL's of the source and target systems are different.

See: Introduction to cloning a Windows NT, Windows 2000, or Windows XP computer

The term "computer type" and "HAL" have the same meaning, and may be interchanged.

How to Determine Your Computers HAL or Type

1. Right click on "My Computer" or Control Panel > System
2. Choose "Properties" from the context menu
3. Click on the Hardware tab
4. Click on the Device Manager button
5. Double-click on "Computer" or click on the + to the left of "Computer."

Possible values for the HAL

• ACPI Multiprocessor PC
• ACPI Uniprocessor PC
• Advanced Configuration and Power Interface (ACPI) PC
• MPS Multiprocessor PC
• MPS Uniprocessor PC
• Standard PC

Possible values for the HAL under Compaq include:

• Compaq SystemPro Multiprocessor or 100% Compatible

Possible values for the HAL under SGI include:

• Silicon Graphics Visual Workstation

Notes:

• If the date of the BIOS is later than 1/1/1999, it is assumed to be a good BIOS and the ACPI HAL is applied during Windows 2000 or XP installation.
• See: How Windows Determines ACPI Compatibility and How Windows XP Determines ACPI Compatibility