Lec 13 - Intel Processors Family

1. THE INTEL PROCESSOR FAMILY

In the late 1970s, Intel introduced the 8086 as its first 16-bit microprocessor. This processor has a 16-bit external bus. The 8086 evolved into a series of faster and more powerful processors starting with the 80286 and ending with the Pentium. The latter was introduced in 1993. This Intel family of processors is usually called the X86 family. Table 1 summarizes the main features of the main members of such a family.















The Intel Pentium processor has about three million transistors and its computational power ranges between two and five times that of its predecessor processor, the 80486. The Pentium family of processors, including the Pentium MMX, Pentium (I, II, III, and IV), has several improvements over its predecessor (Intel’s 80486 processor) that ensure data and code move through the Pentium as fast as possible. One of the most important changes is in the arithmetic logic unit (ALU). The ALU handles all the data, juggling that involves integers, or whole numbers such as 1, 23, 610, 234, or -123. The Pentium is the first Intel processor to have two ALUs so that it can crunch two sets of numbers at the same time. Like the 486, the Pentium has a separate calculation unit that’s optimized for handling floating-point numbers, or numbers with decimal fractions, such as 1.2, 35.8942, or -93.2.
Intel’s Pentium 4 Processor Cache uses a two level cache organization as shown in Figure 1.








The following tables 2 summarize the L1 and L2 Pentium 4 cache performance in terms of the cache hit ratio and cache latency.






You can see the impact of silicon compilation in Figure 2. Intel’s 80386, 80486, and Pentium microprocessors are 32-bit processors, which means that they can manipulate binary numbers as large as 11111111111111111111111111111111, which translates to the decimal number 4,294,967,296, or 4GB (gigabytes). This number represents the upper limit to the amount of memory that the processor—and therefore Windows—can address. The ability to work with 32 bits at a time helps make these PCs work much faster and be able to directly use more memory.