microprocessor
TRANSCRIPT
MICROPROCESSORCENTRAL PROCESSING UNIT
CPU stands for Central Processing Unit. Let us brieflystudy that name:
•It is a processor, because it processes (moves and calculates) data. •It is central, because it is the center of PC data processing. •It is a unit, because it is a chip, which contains millions of transistors.
What is a CPU?
MANUFACTURERS
IBMCYRIX
INTEL CORPORATIONADVANCED MICRO DEVICES(AMD)
BUSa series of connections that carry common signals
a typical processor has two importantbuses for carrying data and
memory--addressing information
data busaddress bus
- data bus -
the bundle of wires (or pins) used to send and receive data
The more signals that can be sentat the same time, the more data canbe transmitted in a specified intervaland, therefore, the faster the bus.
HYBRID DESIGNS
Internal Registers
The size of the internal register isa good indication of how muchinformation the processor can
operate on at one time.
internal data bus
386 to the Pentium--use 32-bit internal registers
8088, 386SX, 386SL – use internal registers twice the width external data bus
386SX 32-bit IR 16-bit data bus386DX 32-bit IR 32-bit data bus
80386
32-bit IR 64-bit data bus
PentiumTwin data pipelines
Address Busthe set of wires that carry theaddressing information used todescribe the memory location towhich the data is being sent, orfrom which the data is being retrieved.
The size (or width) of the address busindicates the maximum amount of RAM
that a chip can address.
The size of the data bus is an indicationof the information-moving capability
of the chip, and the size of theaddress bus tells you how much
memory the chip can handle.
Intel Processor Memory-Addressing Capabilities
6465,53667,108,86468,719,476,73636-bitPentium II
44,0964,194,3044,294,967,29632-bit386DX-Pentium Pro
none1616,38416,777,21624-bit286/386SX
none11,0241,048,57620-bit8088/8086
GbytesMbytes
KilobytesBytesAddress Bus
Processor Family
1 hertz = one cycle per second
The hertz was named for the German physicistHeinrich Rudolph Hertz. In 1885, Hertz confirmed
through experimentation the electromagnetictheory, which states that light is a form of
electromagnetic radiation and is propagated as wave
Processor Speed
A single cycle is the smallest element oftime for the processor. Every action
requires at least one cycle and usuallymultiple cycles. To transfer data to
and from memory, for example, an 8086chip needs four cycles plus wait states.
A wait state is a clock tick in whichNothing happens to ensure that
the processor isn't getting ahead ofthe rest of the computer
A 286 needs only two cycles plus anywait states for the same transfer.
AVERAGE CYCLES PERINSTRUCTION
MICROPROCESSOR
1Pentium
2486
4.5286 and 386
128086 and 8088
100MHz Pentium is about equal to
200MHz 486
400MHz 386 or 286
1,000MHz 8088
664.5xPentium II 300664xPentium II 266663.5xPentium-MMX/Pentium II 233663xPentium/Pentium Pro/MMX 200603xPentium/Pentium Pro 180662.5xPentium/Pentium Pro/MMX 166602.5xPentium 150662xPentium 133602xPentium 120661.5xPentium 100601.5xPentium 90501.5xPentium 75661xPentium 66601xPentium 60
Motherboard SpeedCPU ClockCPU Type/Speed
Table 6.4 Intel Processor and Motherboard Speeds
overclocking Most of the processors running at 50MHz and
higher should have a heat sink installedto prevent the processor from overheating
Microprocessor Progression: IntelThe following table helps you to understand the differences between the different processors that Intel has introduced over the years.
~7,00032 bits64-bit bus3.6 GHz0.09125,000,0002004Pentium 4
"Prescott"
~1,70032 bits64-bit bus1.5 GHz0.1842,000,0002000Pentium 4
~51032 bits64-bit bus450 MHz0.259,500,0001999Pentium III
~30032 bits64-bit bus233 MHz0.357,500,0001997Pentium II
10032 bits64-bit bus60 MHz0.83,100,0001993Pentium
2032 bits25 MHz11,200,000198980486
532 bits16 MHz1.5275,000198580386
116 bits6 MHz1.5134,000198280286
0.3316 bits8-bit bus5 MHz329,00019798088
0.648 bits2 MHz66,00019748080
MIPSData widthClock speedMicronsTransistorsDateName
Transistors is the number of transistors on the chip. You can see that the number of transistors on a single chip has risen steadily over the years. Microns is the width, in microns, of the smallest wire on the chip. For comparison, a human hair is 100 microns thick. As the feature size on the chip goes down, the number of transistors rises. Clock speed is the maximum rate that the chip can be clocked at. Clock speed will make more sense in the next section. Data Width is the width of the ALU. An 8-bit ALU can add/subtract/multiply/etc. two 8-bit numbers, while a 32-bit ALU can manipulate 32-bit numbers. An 8-bit ALU would have to execute four instructions to add two 32-bit numbers, while a 32-bit ALU can do it in one instruction. In many cases, the external data bus is the same width as the ALU, but not always. The 8088 had a 16-bit ALU and an 8-bit bus, while the modern Pentiums fetch data 64 bits at a time for their 32-bit ALUs. MIPS stands for "millions of instructions per second" and is a rough measure of the performance of a CPU. Modern CPUs can do so many different things that MIPS ratings lose a lot of their meaning, but you can get a general sense of the relative power of the CPUs from this column.
Microprocessor History
A microprocessor -- also known as a CPU or central processing unit -- is a complete computation engine that is fabricated on a single chip. The first microprocessor was the Intel 4004, introduced in 1971. The 4004 was not very powerful -- all it could do was add and subtract, and it could only do that 4 bits at a time. But it was amazing that everything was on one chip. Prior to the 4004, engineers built computers either from collections of chips or from discrete components (transistors wired one at a time). The 4004 powered one of the first portable electronic calculators.
The first microprocessor to make it into a home computer was the Intel 8080, a complete 8-bit computer on one chip,introduced in 1974. The first microprocessor to make a real splash in the market was the Intel 8088, introduced in 1979 and incorporated into the IBM PC (which first appeared around 1982). If you are familiar with the PC market and its history, you know that the PC market moved from the 8088 to the 80286 to the 80386 to the 80486 to the Pentium to the Pentium II to the Pentium III to the Pentium 4. All of these microprocessors are made by Intel and all of them are improvements on the basic design of the 8088. The Pentium 4 can execute any piece of code that ran on the original 8088, but it does it about 5,000 times faster!
640K conventional memory barrier
-Total of 1,024K (1mb) addressable location-Upper portion reserved for adapter and system BIOS-Lower portion (640k for DOS and applications)
Intel 8088 and 8086Microprocessor
8088 (1978)- operates at 4.77Mhz (about 4,770,000 ticks or heartbeats per second- 8 bit data bus- used on IBM PCs and XTs (Extended Technology)
8086 (1976)- 16 bit data bus- costly
- increased instruction sets- 80186 (full 16 bit)- 80188 (8 bit)- Both combined on a single chip 15 to 20 of the 8086-8088 series system components (reduced number of components in computer design)- used for highly intelligent peripheral adapter cards, such as network adapters
Intel 80186 and 80188Microprocessor
Two modes of OperationReal-mode- acts essentially the same as an 8086 chip and is fully object-code compatible with the 8086 and 8088
Protected Mode- believed to have access to 1G of memory (including virtual memory)-16Mb of actual addressable memory- it cannot switch from protected mode to real mode without a hardware reset (a warm reboot) - Intel's first attempt to produce a CPU chip that supported multitasking (Windows)
Intel 80286Microprocessor
80286 processor- abbreviated as 286- introduced in 1981- the CPU behind the IBM AT (Advance Technology)- 6Mhz (five times faster than a PC running at 4.77Mhz
- introduced in 1985 - offers greater performance in almost all areas of operation - a full 32-bit processor - 386 can execute the real-mode instructions of an 8086 or 8088, but in fewer clock cycles - additional software capability (modes) and a greatly enhanced Memory Management Unit (MMU). - 386 can switch to and from protected mode under software control without a system reset
Virtual real mode (sometimes called virtual 86 mode) - can run with hardware memory protection while simulating an 8086's real-mode operation
Intel 80386Microprocessor
386DX Processors
- full 32-bit processor- 32-bit internal registers- 32-bit internal data bus- 32-bit external data bus
- 275,000 transistors in a VLSI (Very Large Scale Integration)- 132-pin package- less power requirement than 8086- speed ranges form 16MHz to 33MHz; other manufacturers, primarily AMD and Cyrix, offered comparable versions with speeds up to 40MHz- The 386DX can address 4G of physical memory
386SX Processors
- code named P9 chip - 386 capability at the cost of 286- 16-bit system- can address only up to 16M of memory- speeds at 16 to 33 Mhz- signaled the end of 286 processors- 16MHz 386SX is not markedly faster than a 16MHz 286, but it does offer improved memory-management capabilities
386SL Processors
- low-power CPU- same capabilities as the 386SX- designed for laptop systems in which low power consumption is needed- offer special power-management features (sleep modes)- chip includes an extended architecture that includes a System Management Interrupt (SMI)- the higher transistor count in the SL chips (855,000) compared with even the 386DX processor (275,000 -runs at 25MHz clock speed
Four main features make a given 486 processor roughly twice as fast as an equivalent MHz 386 chip.
These features are:
- Reduced instruction-execution time
Instructions in the 486 take an average of only two clock cycles to complete, compared with an average of more than four cycles on the 386.
Intel 80486Microprocessor
80486- Internal (Level 1) cache
The built-in cache has a hit ratio of 90 to 95 percent, which describes how often zero-wait-state read operations will occur. External caches can improve this ratio further.
- Burst-mode memory cycles
A standard 32-bit (4-byte) memory transfer takes two clock cycles. After a standard 32-bit transfer, more data up to the next 12 bytes (or three transfers) can be transferred with only one cycle used for each 32-bit (4-byte) transfer. Thus, up to 16 bytes of contiguous, sequential memory data can be transferred in as little as five cycles instead of eight cycles or more. This effect can be even greater when the transfers are only 8 bits or 16 bits each
80486
- Built-in (synchronous) enhanced math coprocessor (some versions) (FPU – Floating-point unit)
The math co- processor runs synchronously with the main processor and executes math instructions in fewer cycles than previous designs did. On average, the math coprocessor built into the DX-series chips provides two to three times greater math performance than an external 387 chip.
486 Processors
- about twice as fast as the 386 - easily be upgraded to a DX2 or DX4 processor - the 486 rapidly killed off the 386 - spawned the widespread acceptance of GUIs - speeds from 16MHz all the way up to 120MHz
Intel DX2 and DX4 Operating Speeds versusMotherboard Clock Speeds
N/A120MHz100MHz75MHz60MHz48MHzDX4 (3x mode) speed
N/A100MHz83MHz63MHz50MHz40MHzDX4 (2.5x mode) speed
100MHz80MHz66MHz50MHz40MHz32MHzDX4 (2x mode) speed
N/A80MHz66MHz50MHz40MHz32MHzDX2 processor speed
50MHz40MHz33MHz25MHz20MHz16MHzMotherboard Clock Speed
486DX Processors
- introduced on April 10, 1989 - Two main features
- Integration (math coprocessor,cache controller,cache memory)
- Upgradability (double-speed OverDrive) - 32-bit internal register size- 32-bit external data bus- 32-bit address bus - contains 1.2 million transistors on a piece of silicon no larger than a thumbnail - FPU is 100 percent compatible with 80387 co-processor
486SL Processors
- SL Enhancement refers to a special design that incorporates special power-saving features - designed to be installed in laptop or notebook systems- eventually found their way into desktop systems- incorporates System Management Mode (SMM) - suspend/resume- designed to consume almost no power in the suspend state
486SX Processors
- introduced in April 1991- lower-cost version of the 486 - full DX processor, but the chip does not incorporate the FPU - had a completely different pinout- twice as fast as a 386DX with the same clock speed - normally available in 16, 20, 25, and 33MHz-rated speeds - SX/2 version up to 50 or 66MHz
487SX( Math co-processor)
&Overdrive processors
Built inPentium and thereafter
None80486SX
Built in80486DX
8038780386
8028780286
80878086
FPUCPU
487 SX
- a complete 25MHz 486DX CPU with an extra pin added and some other pins rearranged - provides math coprocessor functionality in the system - prepared its real surprise: the OverDrive processor - any system that supports the 487SX also supports the DX2/OverDrive chips
DX2/OverDriveand DX4 Processors
DX2/OverDrive and DX4 Processors
- March 3, 1992, Intel introduced the DX2 speed-doubling processors- On May 26, 1992, DX2 processors were available in a retail version called OverDrive- Originally, the OverDrive versions of the DX2 were available only in 169-pin versions, which meant that they could be used only with 486SX systems that had sockets configured to support the rearranged pin configuration- On September 14, 1992, Intel introduced 168-pin OverDrive versions for upgrading 486DX systems.- DX2/OverDrive processors run internally at twice the clock rate of the host system - DX2 chip that doesn't run at double speed is the bus interface unit
Vacancy
Table 6.6 Intel 486/Pentium CPU Socket Types and Specifications
Pentium ProVRMdual-pattern SPGA
387Socket 8
Pentium 75-200, Pentium 75+ OverDrive
VRM37x37 SPGA
321Socket 7DX4, 486 Pentium OverDrive3.3v19x19 PGA235Socket 6
Pentium 75-133, Pentium 75+ OverDrive
3.3v37x37 SPGA
320Socket 5
Pentium 60/66, Pentium 60/66 OverDrive
5v21x21 PGA273Socket 4
SX/SX2, DX/DX2, DX4, 486 Pentium OverDrive
5v/3.3v19x19 PGA237Socket 3
SX/SX2, DX/DX2*, DX4 OverDrive, 486 Pentium OverDrive
5v19x19 PGA238Socket 2SX/SX2, DX/DX2*, DX4 OverDrive5v17x17 PGA169Socket 1
Supported ProcessorsVoltagePin LayoutNo. of Pins
Socket Number
ActiveSocket 5/7Pentium 75/90/100Pentium OverDrive with MMX
ActiveSocket 4Pentium 60/6660/66 Pentium OverDrive
ActiveSocket 2 or 3
486SX/DX/SX2/DX2486 Pentium OverDrive
Heat SinkSocketReplacesProcessor Designation
OverDrive Compatibility Problems
Although you can upgrade many older 486SX or 486DXsystems with the OverDrive processors, some exceptionsexist.
Four factors can make an OverDrive upgrade difficultor impossible:
- BIOS routines that use CPU-dependent timing loops- Lack of clearance for the OverDrive heat sink (25MHz and faster)- Inadequate system cooling- A 486 CPU that is soldered in rather than socketed
Pentium®
- October 19, 1992, Intel announced P5 (Pentium) processor - shipped on March 22, 1993- features twin data pipelines (superscalar technology ) u-pipe (primary pipe)- execute all integer and floating-point instructions v-pipe (secondary pipe) - execute only simple integer instructions and certain floating-point instructions pairing - operating on two instructions simultaneously in the different pipes
- one of the first CISC (Complex Instruction Set Computer) chips - Branch Target Buffer (BTB) that employs a technique called branch prediction - SL enhanced (incorporate the SMM)- Built-in FPU- Tape Carrier Packaging
Pentium Processor Specifications
5v (first generation), 3.465v, 3.3v, 3.1v, 2.9v (second generation)Operating voltage:
SMM (System Management Mode), enhanced in second generationPower management:
Built-in FPU (Floating-Point Unit)Math coprocessor:
273-pin PGA, 296-pin SPGA, Tape CarrierExternal package:
0.8 micron (60/66MHz), 0.6 micron (75-100MHz), 0.35 micron (120MHz and up)Circuit size:
3.1 millionNumber of transistors:
YesBurst-mode transfers:
Two-Way Set Associative, Write-Back DataIntegral-cache type:
8K code, 8K dataIntegral-cache size:
4GMaximum memory:
32-bitMemory address bus:
64-bitExternal data bus:
32-bitRegister size:
1x (first generation), 1.5x-3x (second generation)CPU clock multiplier:
60, 66MHz (first generation); 75, 90, 100, 120, 133, 150, 166, 200MHz (second generation)
Maximum rated speeds:
March 22, 1993 (first generation); March 7, 1994 (second generation)Introduced:
Generations of Pentium
First Generation Pentium
- 60 and 66MHz processor speeds- 273-pin PGA form factor and ran on 5v power- ran at the same speed as the motherboard(1x clock)- 0.8-micron BiCMOS process - 3.1 million transistor count
Second Generation Pentium
- March 7, 1994 - 75, 90 and 100MHz versions- Eventually, 120, 133, 150, 166, and 200MHz versions were also introduced - 0.6-micron (75/90/100MHz) BiCMOS technology- 120 and higher MHz second-generation versions incorporate an even smaller die built on a 0.35-micron - run on 3.3v power
Second Generation Pentium
- come in a 296-pin SPGA (Staggered Pin Grid Array) - physically incompatible with the first-generation versions- 3.3 million transistors for additional clock-control SL enhancements on-chip Advanced Programmable Interrupt Controller dual-processor interface (Symmetric Multi-Processing )- use clock-multiplier circuitry - single chip OverDrive upgrade
663xPentium 200
662.5xPentium 166
602.5xPentium 150
662xPentium 133
602xPentium 120
661.5xPentium 100
601.5xPentium 90
501.5xPentium 75
Memory Bus SpeedCPU ClockCPU Type/Speed
Pentium-MMX Processor(Third Generation Pentium)
Third Generation Pentium (MMX)
- code-named P55C - released in January 1997 - incorporates what Intel calls MMX technology - clock rates of 66/166MHz, 66/200MHz, and 66/233MHz - include superscalar architecture, multi-processor support, on-chip local APIC controller, and power management features - New features include a pipelined MMX unit, 16K code and Write-Back cache - 4.5 million transistors - produced on an enhanced 0.35-micron CMOS silicon process which allows for a lower 2.8v voltage level - Socket 7 with VRM (321-pin processor socket)- MMX incorporates a process Intel calls Single Instruction Multiple Data (SIMD) - 57 new instructions (specifically to handle video, audio, and graphics data )
Pentium Pro(Fourth Generation Pentium)
Fourth Generation (Pentium Pro)
- introduced in September of 1995 - 387-pin unit that resides in Socket 8 - Multi-Chip Module (MCM) physical format (Dual Cavity PGA (Pin Grid Array) package )- 36.5 million transistors
Processor Die contains 5.5 million transistors 256K cache die contains 15.5 million transistors512K cache die has 31 million transistors
- includes three internal instruction pipes - Built-in L2 cache- MPS allows configurations of up to four processors running together
Pentium Pro Processor Specifications
3.3vOperating voltage:SMM (System Management Mode)Power management:Built-in FPU (Floating-Point Unit)Math coprocessor:387-pin Dual Cavity PGA (Pin Grid Array)External package:0.35 micronCircuit size:15.5 million (256K cache), 31 million (512K cache)Transistors in L2 cache:5.5 millionNumber of transistors:non-blocking, L1 cacheIntegral-cache type:8K code, 8K dataIntegral-cache size:4GMaximum memory:32-bitMemory address bus:64-bitIntegrated-cache bus:64-bitExternal data bus:32-bitRegister size:2.5x-3xCPU clock multiplier:150, 166, 180, 200MHzMaximum rated speeds:September 1995Introduced:
Pentium II
- code name "Klamath - May 1997- Single Edge Contact (SEC) cartridge - Pentium II 266MHz chip is more than twice as fast as a classic Pentium 200MHz - a Pentium Pro with MMX technology instructions - 0.35 micron - incorporates Dual Independent Bus architecture (one for accessing the L2 cache, the other for accessing main memory )
665xPentium II 333
664.5xPentium II 300
664xPentium II 266
663.5xPentium II 233
Motherboard Speed
CPU Clock
CPU Type/Speed
2.8vOperating voltage:
SMM (System Management Mode)Power management:
Built-in FPU (Floating-Point Unit)Math coprocessor:
242-pin Single Edge CartridgeExternal package:
0.35 micronCircuit size:
31 millionTransistors in L2 cache:
512KL2 cache size:
7.5 millionNumber of transistors:
non-blocking, L1 cacheIntegral-cache type:
16K code, 16K dataIntegral-cache size:
64GMaximum memory:
32-bitMemory address bus:
64-bitIntegrated-cache bus:
64-bitExternal data bus:
300-bitInternal bus width:
3.5x,4x-4.5xCPU clock multiplier:
233, 266, 300MHzMaximum rated speeds:
May 1997Introduced:
Pentium II Processor Specifications
Performance Headroom for the Applications You Need
Whether you're into media, PC imaging, or communications, the Pentium II processor has plenty of special product features to meet your needs:
100MHz Front Side Bus (available with 450MHz, 400MHz and 350MHz) Dual Independent Bus architecture (D.I.B.) Dynamic Execution Intel MMX™ technology Single Edge Contact Cartridge (S.E.C.C.)
Fact Sheet
In fact the Pentium III contained two rather different news items, one small and one somewhat bigger. Intel's new top processor is a Pentium II in principle. It is mounted in a BX based motherboard with Slot 1. This processor has some built-infeatures:
A rather problematic ID numbering. New registers and 70 new instructions.
Finally the clock speed was raised to 500 MHz with room forfurther increases. Pentium III Xeon (code name Tanner) wasintroduced March 17th, 1999. It was a Xeon chip updated withall the new features from Pentium III. To utilize it Intel has the840 chipset.
Two new features
-System scalability up to 64 GB- 400 MHz Front Side Bus of 128 bit width - 20 KB L1 cache and 256 KB L2 - The ALU (Arithmetical Logic Unit) runs at twice the clock speed
- Intel® MMX™ media enhancement technology - Internet Streaming SIMD Extensions - Compatible with Intel® Architecture-based software - 0.13 or 0.18 micron technology - Intel® NetBurst™ micro-architecture - PGA-423 and mPGA-478 form factors - Speeds up to 2.20 GHz
Processor Highlights
- A new socket for simple motherboard design - Clock frequencies from 1500 MHz - 20 stages pipeline - SSE2 and 128 bit MMX - 42 millions of transistors - A new 423 pins socket design - Dual Rambus memory channel with i850 chipset - Only single processor mode available.
Processor Highlights ( continued)
NetBURST
Intel uses the term NetBURST to describe some features in Pentium 4:
Advanced Dynamic Execution The Rapid Execution Engine
Advanced Dynamic Execution means that the processor may execute up to 6 instructions simultanously.
Using Rapid Execution Engine certain instructions may be executed at twicethe normal speed.
A 'Willamette' core Pentium 4.
"Northwood" core Pentium 4 processor. (P4A)
“Willamette”
•1.4 and 1.5 GHz•released in November 2000 •Socket 423 , later revisions moving to socket 478 •100 MHz Quad-pumped (400Mhz FSB)•sacrificed per-cycle performance in order to gain two things: very high clockspeeds, and SSE performance •also comes in a low-end Celeron version (often referred to as Celeron 4) and a high-end Xeon version intended for SMP configurations.
A 'Northwood' core Pentium 4 processor (P4A)
•2.0 , 2.2 , 2.4, 2.8 GHz•3.06 GHz processor supported Hyper-threading (800FSB)•400 MHz to 533 MHz FSB•released in January 2002 •combined an increase in the secondary cache size from 256k to 512k •0.13 micron or 130nm)•socket 478 (socket 423 with adapters)•3.2 GHz variant was launched in June and a final 3.4 GHz version wa launched in early 2004
Extreme Edition 3.73 GHz - Top Extreme Edition 3.73 GHz - Bottom
Pentium 4 Extreme Edition (P4EE) •2 MB of Level 3 cache •Socket 478 form factor , LGA775 version is also available•In office applications, the Extreme Edition was generally a bit slower than the Northwood •Some games benefited from the added cache, particularly those based on the Quake III and Unreal engines •improved most in multimedia encoding•bus speed from 800 MHz to 1066MHz •Only one Gallatin-based chip at 3.46 GHz was released before the Extreme Edition was migrated to the Prescott core
A ‘Prescott' core Pentium 4.
Prescott
•90nm process•clocked at the same rate as a Northwood •benchmarks show that a Northwood runs slightly faster than a Prescott •Currently, 3.8 GHz is the fastest Prescott-based processor •from Socket 478 to LGA775 •LGA775 reference cooler and mounting system were somewhat better designs •thermal problems were so severe •Intel decided to abandon the Prescott architecture altogether, and attempts to roll out a 4 GHz •showed in extreme cases it took a 5.2 GHz Prescott core to match the performance of an Athlon FX-55 that clocked at 2.6 GHz
Dual Core Pentium 4
•marketed as the Pentium D 8xx •reputed to have a 60-80% increase in performance per clock-speed •launched May 2005 •Dubbed the “Smithfield” core •two connected Prescott cores
Dual Core Pentium 4
22,000,000 37,000,000 42,000,000
1999 2000 2001
AMD original Athlon AMD Athlon Thunderbird
Pentium 4
7th. Generation
27,400,000 18,900,000 9,300,000
? 28,000,000
1999 Mobile Pentium II Mobile Celeron
Pentium III AMD K6-3
Pentium III CuMine
Improved 6th. Generation
5,500,000 8,800,000 7,500,000 9,300,000
1995 1997 1997 1998
Pentium Pro AMD K6
Pentium II AMD K6-2
6th. Generation
4,500,000 6,000,000 6,000,000
1997 1997 1998
Pentium MMX IBM/Cyrix 6x86MX IDT WinChip2 3D
Improved 5th. Generation
3,100,000 -- --
3,500,000
1993-95 1996 1996 1997
Pentium Cyrix 6X86
AMD K5 IDT WinChip C6
5th. Generation
1,200,0001990-9280486SX, 80486DX, 80486DX2 and 80486DX4
4th. Generation
275,0001987-8880386DX and 80386SX3rd. Generation
134,0001984802862nd. Generation
29,0001978-818086 and 80881st. Generation
Number of transistors
YearCPUsPC
Graphic overview of the processors