Editing System requirements (section)

== Hardware requirements ==

The most common set of requirements defined by any [[operating system]] or [[software application]] is the physical computer resources, also known as [[Computer hardware|hardware]], A hardware requirements list is often accompanied by a [[hardware compatibility list]] (HCL), especially in case of operating systems. An HCL lists tested, compatible, and sometimes incompatible hardware devices for a particular operating system or application. The following sub-sections discuss the various aspects of hardware requirements.

=== Architecture ===

All computer [[operating system]]s are designed for a particular [[computer architecture]]. Most software applications are limited to particular operating systems running on particular architectures. Although architecture-independent operating systems and applications exist, most need to be recompiled to run on a new architecture. See also a list of [[Comparison of operating systems#Technical information|common operating systems]] and their supporting architectures.

=== Processing power ===

The power of the [[central processing unit]] (CPU) is a fundamental system requirement for any software. Most software running on [[x86 architecture]] define processing power as the [[List of microprocessors|model]] and the [[Clock rate|clock speed]] of the CPU. Many other features of a CPU that influence its speed and power, like [[Front side bus|bus speed]], [[CPU cache|cache]], and [[Instructions per second|MIPS]] are often ignored. This definition of power is often erroneous, as different makes and models of CPUs at similar clock speed often have [[Megahertz myth|different throughput speeds]].

=== Memory ===

All software, when run, resides in the [[random access memory]] (RAM) of a computer. Memory requirements are defined after considering demands of the application, operating system, supporting software and files, and other running processes. Optimal performance of other unrelated software running on a multi-tasking computer system is also considered when defining this requirement.

=== Secondary storage ===

Data storage device requirements vary, depending on the size of software installation, temporary files created and maintained while installing or running the software, and possible use of [[Virtual memory|swap space]] (if RAM is insufficient).

=== Display adapter ===

Software requiring a better than average [[computer graphics]] display, like [[Graphics software|graphics editors]] and high-end [[Video game|games]], often define high-end [[Graphics processing unit|display adapters]] in the system requirements.

=== Peripherals ===

Some software applications need to make extensive and/or special use of some [[peripheral]]s, demanding the higher performance or functionality of such peripherals. Such peripherals include [[CD-ROM|CD-ROM drives]], [[Computer keyboard|keyboards]], [[pointing device]]s, [[Computer networking device|network devices]], etc.