A type of video adapter that contains its own processor to boost performance levels. These processors are specialized for computing graphical transformations, so they achieve better results than the general-purpose CPU used by the computer. In addition, they free up the computer’s CPU to execute other commands while the graphics accelerator is handling graphics computations.
The popularity of graphical applications, and especially multimedia applications, has made graphics accelerators not only a common enhancement, but a necessity. Most computer manufacturers now bundle a graphics accelerator with their mid-range and high-end systems.
Aside from the graphics processor used, the other characteristics that differentiate graphics accelerators are:
memory : Graphics accelerators have their own memory, which is reserved for storing graphical representations. The amount of memory determines how much resolution and how many colors can be displayed. Some accelerators use conventional DRAM, but others use a special type of video RAM (VRAM), which enables both the video circuitry and the processor to simultaneously access the memory.
bus : Each graphics accelerator is designed for a particular type of video bus. As of 1995, most are designed for the PCI bus.
register width: The wider the register, the more data the processor can manipulate with each instruction. 64-bit accelerators are already becoming common, and we can expect 128-bit accelerators in the near future.
- graphics based
)Refers to software and hardware that treat objects on a display screen as bit maps or geometrical shapes rather than as characters. In contrast, character-based systems treat everything as ASCII or extended ASCII characters. All graphics software is by definition graphics based. Systems that manipulate text can also be graphics based; for example, desktop publishing […]
- graphics character
A character that represents a shape. By combining graphics characters, even character-mode programs can display rudimentary graphics, known as block graphics. Many of the characters in the extended ASCII character set are graphics characters.
- graphics coprocessor
A microprocessor specially designed for handling graphics computations. Most graphics accelerators include a graphics coprocessor.
- graphics display system
The combination of monitor and video adapter that makes a computer capable of displaying graphics.
- graphics file formats
A file format designed specifically for representing graphical images. Graphics file formats can be broadly categorized into bit-mapped formats and vector formats.