Chapter 7:C P U (microprocessors)
CPU
The processor, also called the microprocessor or CPU (for Central Processing Unit), is the
brain of the PC. It performs all general computing tasks and coordinates tasks done by
memory, video, disk storage, and other system components. The CPU is a very complex chip
with millions of transitors integraeted on it. CPU resides directly on the motherboard of
most PCs, but may instead reside on a daughtercard that connects to the motherboard via a
dedicated specialized CPU slot.
Intel Processors
Intel makes a family of processors
– X286,X386,X486,Pentium I ,Pentium 2, Pentium 3 ,Pentium 4 processors in
most PCs
– Celeron processor sold for low-cost PCs
– Xeon and Itanium for high-end workstations and network servers
– DualCore, Core2duo,QuadCore,i3,i5,i7 server processor series.
Mobile processors
Laptops with the Intel Core processor family are designed to power convenient, ultra-thin
designs while enabling greater mobile performance.
Intel Core i7 mobile processor Extreme Edition
Intel Core i7 processor
Intel Core i5 processor
Intel Core i3 processor
Workstation and desktop processors
Automatically adjusting to your unique workloads, workstations, and desktops powered by
the Intel Xeon and Intel Core processor families deliver the smart performance you need at
home and in the office.
Intel desktop processors
Intel Core i7 processor Extreme Edition
Intel Core i7 processor
Intel Core i5 processor
Intel Core i3 processor
Server processors
Powerful range of multi-core 64-bit servers, Intel server processors offer the scalable
performance and advanced reliability you need for your server and data center
environments.
Intel Xeon processor 7000 sequence
Intel Xeon processor 5000 sequence
Intel Xeon processor 3000 sequence
Intel Itanium processor 9000 sequence
Additional processor technologies
Intel Atom processors
Intel Architecture Processors
Intel Network Infrastructure Processors
Intel I/O processors (Intel IOP)
Other processors
– Cyrix and AMD make Intel-compatible microprocessors
– PowerPC chips used primarily in Macintosh computers
– HP’s Alpha microprocessor used in high-end servers
Components of the CPU
• Control unit:- Moves data and instructions between main memory and registers
• Arithmetic logic unit (ALU):- Performs computation and comparison operations
• Set of registers:- Storage locations that hold inputs and outputs for the ALU
Actions Performed by CPU
Fetch cycle : CPU:
• Fetches an instruction from primary storage
• Increments a pointer to location of next instruction
• Separates instruction into components (instruction code and data inputs)Stores
each component in a separate register
Execution cycle : ALU:
• Retrieves instruction code from a register
• Retrieves data inputs from registers
• Passes data inputs through internal circuits to perform data transformation Stores
results in a
register
Processor Memory Hierarchy
Processor Speed
The processor clock coordinates all CPU and memory operations by periodically generating a
time reference signal called a clock cycle or tick. Clock frequency is specified in megahertz
(MHz), which specifies millions of ticks per second, or gigahertz (GHz), which specifies
billions of ticks per second. Clock speed determines how fast instructions execute. Some
instructions require one tick, others multiple ticks, and some processors execute multiple
instructions during one tick. The number of ticks per instruction varies according to
processor architecture, its instruction set, and the specific instruction. Complex Instruction
Set Computer (CISC) processors use complex instructions. Each requires many clock cycles
to execute, but accomplishes a lot of work. Reduced Instruction Set Computer (RISC)
processors use fewer, simpler instructions. Each takes few ticks but accomplishes relatively
little work
Live Practicle
