In computer architecture, 32-bit integers, memory addresses, or other data units are those that are 32 bits (4 octets or 4 Bytes) wide. Also, 32-bit CPU and ALU architectures are those that are based on registers, address buses, or data buses of that size. 32-bit microcomputers are computers in which 32-bit microprocessors are the norm. We know that n-bit microprocessor can handle n-bit word size.
As n-bit register can store 2n different values so, a 32-bit register can store 232 different values. The range of integer values that can be stored in 32 bits depends on the integer representation used. We know there are two most common representations for integer data. And they are Unsigned and Signed representations. The range is 0 through 4,294,967,295 (232 − 1) for representation as an Unsigned binary number, and −2,147,483,648 (−231) through 2,147,483,647 (231 − 1) for representation as two's complement Signed numbers.
One important consequence is that a processor with 32-bit memory addresses can directly access at most 4 GB of byte-addressable memory. But due to some issues, though in practice the limit may be lower.
There were multiple instances of 32-bit microprocessors. As examples, we can consider following
In 1985, Intel announced the 80386 a 32-bit microprocessor with 2,75,000 transistors. It supported multitasking.
Intel 486 microprocessor was the first to offer a built-in math co-processor introduced in the year 1989. It had 1.2 million transistors inside it.
Intel Pentium microprocessor with 3.1 million transistors was introduced in the year 1993. It allowed computers to process real-world data like speech, sound, handwriting and photographic images.
In the year 1997, the 7.5-million transistor Intel Pentium II microprocessor was designed specifically to process audio, video and graphics data efficiently.
In the year 1999, Intel Celeron processors range designed for the value PC market segment were released.
Intel Pentium III processors with 9.5 million transistors designed for streaming audio, , video and speech recognition applications, advanced imaging, 3D and Intel Pentium III Xeon processors for workstation and server market segments were introduced in 1999.
Intel Pentium IV processors with more than 42 million transistors introduced from 2000 are used in the present PCs. In such computers, users can deliver TV-like video via the internet, communicate with real-time video, create professional quality movies and voice, render 3D graphics in real time, quickly encode music for MP3 players and can concurrently run several multimedia applications when the system is connected to the Internet.
Introduced from 2001, Intel Xeon processors are targeted for high-performance and mid-range, dual-processor workstations, dual and multiprocessor server configurations coming in the range.