PC/System requirements

As PCs are made of many interchangeable components, they can run games with differing levels of performance — unlike video game consoles, where the components are fixed, and so a certain level of performance is guaranteed for each game.

The main three system specifications which affect game performance are:
 * the CPU frequency (in Hertz), which is the number of operations the processor can do per second;
 * the amount of RAM (in bytes), which is the amount of working space available for a game;
 * and the amount of video RAM (in bytes), which is the amount of working space available on the graphics card, for storing textures.

Each of these affects game performance in a different way, but if they're below the recommended specifications for a game, that game is unlikely to run well, or even at all in some cases.

Additionally, there are various other parameters which can affect whether you can install or play a game on a computer:
 * the amount of disk space required (in bytes) affects whether game can be installed fully, partially, or at all;
 * the optical drive speed (units explained here) affects the data transfer rate if the game's running off an optical disc;
 * your internet data transfer rate decides whether you can play online or not, and some games require an internet connection;
 * your operating system version decides whether a game executable will run on the computer, with games being written and compiled for specific versions of operating systems or their libraries;
 * and your DirectX version affects whether a game using DirectX will run on Windows — many games use features only available in certain versions of DirectX or higher.

Measuring specifications
On StrategyWiki, any game which has its system requirements available will have them displayed in the infobox on the guide's main page, in a section similar to the one on the right here. Each system requirement is shown with a bar displaying how it relates to a modern average gaming PC. In order, the specifications are (with maximum values):
 * CPU frequency (max: 3000MHz)
 * Amount of RAM (max: 2048MiB)
 * Amount of disk space (max: 10240MiB)
 * Amount of video RAM (max: 1024MiB)
 * Internet data transfer rate (max: 8192Kibps)
 * Optical drive speed (max: 52x)
 * DirectX version (max: 10)
 * Windows version ("98", "Me", "2000", "XP", "XP (SP2)" or "Vista")
 * OS X version
 * Linux version (generally information about kernel and glibc compatibility)