Types of central processing units (CPUs)

What
is
a
CPU?

The

central
processing
unit
(CPU)
is
the
computer’s
brain.
It
handles
the
assignment
and
processing
of
tasks
and
manages
operational
functions
that
all
types
of
computers
use.

CPU
types
are
designated
according
to
the
kind
of
chip
that
they
use
for
processing
data.
There’s
a
wide
variety
of
processors
and
microprocessors
available,
with
new
powerhouse
processors
always
in
development.
The
processing
power
CPUs
provide
enables
computers
to
engage
in
multitasking
activities.
Before
discussing
the
types
of
CPUs
available,
we
should
clarify
some
basic
terms
that
are
essential
to
our
understanding
of
CPU
types.

Key
CPU
terms

There
are
numerous
components
within
a
CPU,
but
these
aspects
are
especially
critical
to
CPU
operation
and
our
understanding
of
how
they
operate:

• 
  Cache:
  When
  it
  comes
  to
  information
  retrieval,
  memory
  caches
  are
  indispensable.
  Caches
  are
  storage
  areas
  whose
  location
  allows
  users
  to
  quickly
  access
  data
  that’s
  been
  in
  recent
  use.
  Caches
  store
  data
  in
  areas
  of
  memory
  built
  into
  a
  CPU’s
  processor
  chip
  to
  reach
  data
  retrieval
  speeds
  even
  faster
  than
  random
  access
  memory
  (RAM)
  can
  achieve.
  Caches
  can
  be
  created
  through
  software
  development
  or
  hardware
  components.

• 
  Clock
  speed:
  All
  computers
  are
  equipped
  with
  an
  internal
  clock,
  which
  regulates
  the
  speed
  and
  frequency
  of
  computer
  operations.
  The
  clock
  manages
  the
  CPU’s
  circuitry
  through
  the
  transmittal
  of
  electrical
  pulses.
  The
  delivery
  rate
  of
  those
  pulses
  is
  termed
  clock
  speed,
  which
  is
  measured
  in
  Hertz
  (Hz)
  or
  megahertz
  (MHz).
  Traditionally,
  one
  way
  to
  increase
  processing
  speed
  has
  been
  to
  set
  the
  clock
  to
  run
  faster
  than
  normal.

• 
  Core:
  Cores
  act
  as
  the
  processor
  within
  the
  processor.
  Cores
  are
  processing
  units
  that
  read
  and
  carry
  out
  various
  program
  instructions.
  Processors
  are
  classified
  according
  to
  how
  many
  cores
  are
  embedded
  into
  them.
  CPUs
  with
  multiple
  cores
  can
  process
  instructions
  considerably
  faster
  than
  single-core
  processors.
  (Note:
  The
  term
  “Intel®
  Core™”
  is
  used
  commercially
  to
  market
  Intel’s
  product
  line
  of
  multi-core
  CPUs.)

• 
  Threads:
  Threads
  are
  the
  shortest
  sequences
  of
  programmable
  instructions
  that
  an
  operating
  system’s
  scheduler
  can
  independently
  administer
  and
  send
  to
  the
  CPU
  for
  processing.
  Through
  multithreading—the
  use
  of
  multiple
  threads
  running
  simultaneously—a
  computer
  process
  can
  be
  run
  concurrently.
  Hyper-threading
  refers
  to
  Intel’s
  proprietary
  form
  of
  multithreading
  for
  the
  parallelization
  of
  computations.

Other
components
of
the
CPU

In
addition
to
the
above
components,
modern
CPUs
typically
contain
the
following:

• 
  Arithmetic
  logic
  unit
  (ALU):
  Carries
  out
  all
  arithmetic
  operations
  and
  logical
  operations,
  including
  math
  equations
  and
  logic-based
  comparisons.
  Both
  types
  are
  tied
  to
  specific
  computer
  actions.
• 
  Buses:
  Ensures
  proper
  data
  transfer
  and
  data
  flow
  between
  components
  of
  a
  computer
  system.
• 
  Control
  unit:
  Contains
  intensive
  circuitry
  that
  controls
  the
  computer
  system
  by
  issuing
  a
  system
  of
  electrical
  pulses
  and
  instructs
  the
  system
  to
  carry
  out
  high-level
  computer
  instructions.
• 
  Instruction
  register
  and
  pointer:
  Displays
  location
  of
  the
  next
  instruction
  set
  to
  be
  executed
  by
  the
  CPU.
• 
  Memory
  unit:
  Manages
  memory
  usage
  and
  the
  flow
  of
  data
  between
  RAM
  and
  the
  CPU.
  Also,
  the
  memory
  unit
  supervises
  the
  handling
  of
  cache
  memory.
• 
  Registers:
  Provides
  built-in
  permanent
  memory
  for
  constant,
  repeated
  data
  needs
  that
  must
  be
  handled
  regularly
  and
  immediately.

How
do
CPUs
work?

CPUs
use
a
type
of
repeated
command
cycle
that’s
administered
by
the
control
unit
in
association
with
the
computer
clock,
which
provides
synchronization
assistance.

The
work
a
CPU
does
occurs
according
to
an
established
cycle
(called
the
CPU
instruction
cycle).
The
CPU
instruction
cycle
designates
a
certain
number
of
repetitions,
and
this
is
the
number
of
times
the
basic
computing
instructions
will
be
repeated,
as
enabled
by
that
computer’s
processing
power.

The
three
basic
computing
instructions
are
as
follows:

• 
  Fetch:
  Fetches
  occur
  anytime
  data
  is
  retrieved
  from
  memory.
• 
  Decode:
  The
  decoder
  within
  the
  CPU
  translates
  binary
  instructions
  into
  electrical
  signals,
  which
  engage
  with
  other
  parts
  of
  the
  CPU.
• 
  Execute:
  Execution
  occurs
  when
  computers
  interpret
  and
  carry
  out
  a
  computer
  program’s
  set
  of
  instructions.

Basic
attempts
to
generate
faster
processing
speeds
have
led
some
computer
owners
to
forego
the
usual
steps
involved
in
creating
high-speed
performance,
which
normally
require
the
application
of
more
memory
cores.
Instead,
these
users
adjust
the
computer
clock
so
it
runs
faster
on
their
machine(s).
The
“overclocking”
process
is
analogous
to
“jailbreaking”
smartphones
so
their
performance
can
be
altered.
Unfortunately,
like
jailbreaking
a
smartphone,
such
tinkering
is
potentially
harmful
to
the
device
and
is
roundly
disapproved
by
computer
manufacturers.

Types
of
central
processing
units

CPUs
are
defined
by
the
processor
or
microprocessor
driving
them:

• 
  Single-core
  processor:
  A
  single-core
  processor
  is
  a
  microprocessor
  with
  one
  CPU
  on
  its
  die
  (the
  silicon-based
  material
  to
  which
  chips
  and
  microchips
  are
  attached).
  Single-core
  processors
  typically
  run
  slower
  than
  multi-core
  processors,
  operate
  on
  a
  single
  thread
  and
  perform
  the
  instruction
  cycle
  sequence
  only
  once
  at
  a
  time.
  They
  are
  best
  suited
  to
  general-purpose
  computing.
• 
  Multi-core
  processor:
  A
  multi-core
  processor
  is
  split
  into
  two
  or
  more
  sections
  of
  activity,
  with
  each
  core
  carrying
  out
  instructions
  as
  if
  they
  were
  completely
  distinct
  computers,
  although
  the
  sections
  are
  technically
  located
  together
  on
  a
  single
  chip.
  For
  many
  computer
  programs,
  a
  multi-core
  processor
  provides
  superior,
  high-performance
  output.
• 
  Embedded
  processor:
  An
  embedded
  processor
  is
  a
  microprocessor
  expressly
  engineered
  for
  use
  in
  embedded
  systems.
  Embedded
  systems
  are
  small
  and
  designed
  to
  consume
  less
  power
  and
  be
  contained
  within
  the
  processor
  for
  immediate
  access
  to
  data.
  Embedded
  processors
  include
  microprocessors
  and
  microcontrollers.
• 
  Dual-core
  processor:
  A
  dual-core
  processor
  is
  a
  multi-core
  processor
  containing
  two
  microprocessors
  that
  act
  independently
  from
  each
  other.
• 
  Quad-core
  processor:
  A
  quad-core
  processor
  is
  a
  multi-core
  processor
  that
  has
  four
  microprocessors
  functioning
  independently.
• 
  Octa-core:
  An
  octa-core
  processor
  is
  a
  multi-core
  processor
  that
  has
  eight
  microprocessors
  functioning
  independently.
• 
  Deca-core
  processor:
  A
  deca-core
  processor
  is
  an
  integrated
  circuit
  that
  has
  10
  cores
  on
  one
  die
  or
  per
  package.

Leading
CPU
manufacturers
and
the
CPUs
they
make

Although
several
companies
manufacture
products
or
develop
software
that
supports
CPUs,
that
number
has
dwindled
down
to
just
a
few
major
players
in
recent
years.

The
two
major
companies
in
this
area
are
Intel
and
Advanced
Micro
Devices
(AMD).
Each
uses
a
different
type
of
instruction
set
architecture
(ISA).
Intel
processors
use
a
complex
instruction
set
computer
(CISC)
architecture.
AMD
processors
follow
a
reduced
instruction
set
computer
(RISC)
architecture.

• 
  Intel:
  Intel
  markets
  processors
  and
  microprocessors
  through
  four
  product
  lines.
  Its
  premium,
  high-end
  line
  is
  Intel
  Core.
  Intel’s
  Xeon®
  processors
  are
  targeted
  toward
  offices
  and
  businesses.
  Intel’s
  Celeron®
  and
  Intel
  Pentium®
  lines
  are
  considered
  slower
  and
  less
  powerful
  than
  the
  Core
  line.

• 
  Advanced
  Micro
  Devices
  (AMD):
  AMD
  sells
  processors
  and
  microprocessors
  through
  two
  product
  types:
  CPUs
  and
  APUs
  (which
  stands
  for
  accelerated
  processing
  units).
  APUs
  are
  CPUs
  that
  have
  been
  equipped
  with
  proprietary
  Radeon™
  graphics.
  AMD’s
  Ryzen™
  processors
  are
  high-speed,
  high-performance
  microprocessors
  intended
  for
  the
  video
  game
  market.
  Athlon™
  processors
  was
  formerly
  considered
  AMD’s
  high-end
  line,
  but
  AMD
  now
  uses
  it
  as
  a
  basic
  computing
  alternative.

• 
  Arm:
  Although
  Arm
  doesn’t
  actually
  manufacture
  equipment,
  it
  does
  lease
  out
  its
  valued,
  high-end
  processor
  designs
  and/or
  other
  proprietary
  technologies
  to
  other
  companies
  who
  do
  make
  equipment.
  Apple,
  for
  example,
  no
  longer
  uses
  Intel
  chips
  in
  Mac®
  CPUs
  but
  makes
  its
  own
  customized
  processors
  based
  on
  Arm
  designs.
  Other
  companies
  are
  following
  this
  example.

Related
CPU
and
processor
concepts

Graphics
processing
unit
(GPUs)

While
the
term
“graphics
processing
unit”
includes
the
word
“graphics,”
this
phrasing
does
not
truly
capture
what
GPUs
are
about,
which
is
speed.
In
this
instance,
its
increased
speed
is
the
cause
of
accelerating
computer
graphics.

The

GPU
is
a
type
of
electronic
circuit
with
immediate
applications
for
PCs,
smartphones
and
video
game
consoles,
which
was
their
original
use.
Now
GPUs
also
serve
purposes
unrelated
to
graphics
acceleration,
like
cryptocurrency
mining
and
the
training
of

neural
networks.

Microprocessors

The
quest
for
computer
miniaturization
continued
when

computer
science
created
a
CPU
so
small
that
it
could
be
contained
within
a
small
integrated
circuit
chip,
called
the
microprocessor.
Microprocessors
are
designated
by
the
number
of
cores
they
support.

A
CPU
core
is
“the
brain
within
the
brain,”
serving
as
the
physical
processing
unit
within
a
CPU.
Microprocessors
can
contain
multiple
processors.
Meanwhile,
a
physical
core
is
a
CPU
built
right
into
a
chip,
but
which
only
occupies
one
socket,
thus
enabling
other
physical
cores
to
tap
into
the
same
computing
environment.

Output
devices

Computing
would
be
a
vastly
limited
activity
without
the
presence
of
output
devices
to
execute
the
CPU’s
sets
of
instruction.
Such
devices
include
peripherals,
which
attach
to
the
outside
of
a
computer
and
vastly
increase
its
functionality.

Peripherals
provide
the
means
for
the
computer
user
to
interact
with
the
computer
and
get
it
to
process
instructions
according
to
the
computer
user’s
wishes.
They
include
desktop
essentials
like
keyboards,
mice,
scanners
and
printers.

Peripherals
are
not
the
only
attachments
common
to
the
modern
computer.
There
are
also
input/output
devices
in
wide
use
and
they
both
receive
information
and
transmit
information,
like
video
cameras
and
microphones.

Power
consumption

Several
issues
are
impacted
by
power
consumption.
One
of
them
is
the
amount
of
heat
produced
by
multi-core
processors
and
how
to
dissipate
excess
heat
from
that
device
so
the
computer
processor
remains
thermally
protected.
For
this
reason,

hyperscale
data
centers
(which
house
and
use
thousands
of
servers)
are
designed
with
extensive
air-conditioning
and
cooling
systems.

There
are
also
questions
of
sustainability,
even
if
we’re
talking
about
a
few
computers
instead
of
a
few
thousand.
The
more
powerful
the
computer
and
its
CPUs,
the
more
energy
will
be
required
to
support
its
operation—and
in
some
macro-sized
cases,
that
can
mean
gigahertz
(GHz)
of
computing
power.

Specialized
chips

The
most
profound
development
in
computing
since
its
origins,

artificial
intelligence
(AI)
is
now
impacting
most
if
not
all
computing
environments.
One
development
we’re
seeing
in
the
CPU
space
is
the
creation
of
specialty
processors
that
have
been
built
specifically
to
handle
the
large
and
complex

workloads
associated
with
AI
(or
other
specialty
purposes):

• Such
  equipment
  includes
  the
  Tensor
  Streaming
  Processor
  (TSP),
  which
  handles
  
  machine
  learning
  (ML)
  tasks
  in
  addition
  to
  AI
  applications.
  Other
  products
  equally
  suited
  to
  AI
  work
  are
  the
  AMD
  Ryzen
  Threadripper™
  3990X
  64-Core
  processor
  and
  the
  Intel
  Core
  i9-13900KS
  Desktop
  Processor,
  which
  uses
  24
  cores.
• For
  an
  application
  like
  video
  editing,
  many
  users
  opt
  for
  the
  Intel
  Core
  i7
  14700KF
  20-Core,
  28-thread
  CPU.
  Still
  others
  select
  the
  Ryzen
  9
  7900X,
  which
  is
  considered
  AMD’s
  best
  CPU
  for
  video
  editing
  purposes.
• In
  terms
  of
  video
  game
  processors,
  the
  AMD
  Ryzen
  7
  5800X3D
  features
  a
  3D
  V-Cache
  technology
  that
  helps
  it
  elevate
  and
  accelerate
  game
  graphics.
• For
  general-purpose
  computing,
  such
  as
  running
  an
  OS
  like
  Windows
  or
  browsing
  multimedia
  websites,
  any
  recent-model
  AMD
  or
  Intel
  processor
  should
  easily
  handle
  routine
  tasks.

Transistors

Transistors
are
hugely
important
to
electronics
in
general
and
to
computing
in
particular.
The
term
is
a
mix
of
“transfer
resistance”
and
typically
refers
to a
component
made
of
semiconductors
used
to
limit
and/or
control
the
amount
of
electrical
current
flowing
through
a
circuit.

In
computing,
transistors
are
just
as
elemental.
The
transistor
is
the
basic
building
unit
behind
the
creation
of
all
microchips.
Transistors
help
comprise
the
CPU,
and
they’re
what
makes
the
binary
language
of
0s
and
1s
that
computers
use
to
interpret
Boolean
logic.

The
next
wave
of
CPUs

Computer
scientists
are
always
working
to
increase
the
output
and
functionality
of
CPUs.
Here
are
some
projections
about
future
CPUs:

• 
  New
  chip
  materials:
  The
  silicon
  chip
  has
  long
  been
  the
  mainstay
  of
  the
  computing
  industry
  and
  other
  electronics.
  The
  
  new
  wave
  of
  processors
  (link
  resides
  outside
  ibm.com)
  will
  take
  advantage
  of
  new
  chip
  materials
  that
  offer
  increased
  performance.
  These
  include
  carbon
  nanotubes
  (which
  display
  excellent
  thermal
  conductivity
  through
  carbon-based
  tubes
  approximately
  100,000
  times
  smaller
  than
  the
  width
  of
  a
  human
  hair),
  graphene
  (a
  substance
  that
  possesses
  outstanding
  thermal
  and
  electrical
  properties)
  and
  spintronic
  components
  (which
  rely
  on
  the
  study
  of
  the
  way
  electrons
  spin,
  and
  which
  could
  eventually
  produce
  a
  spinning
  transistor).
• 
  Quantum
  over
  binary:
  Although
  current
  CPUs
  depend
  on
  the
  use
  of
  a
  binary
  language,
  
  quantum
  computing
  will
  eventually
  change
  that.
  Instead
  of
  binary
  language,
  quantum
  computing
  derives
  its
  core
  principles
  from
  quantum
  mechanics,
  a
  discipline
  that
  has
  revolutionized
  the
  study
  of
  physics.
  In
  quantum
  computing,
  binary
  digits
  (1s
  and
  0s)
  can
  exist
  in
  multiple
  environments
  (instead
  of
  in
  two
  environments
  currently).
  And
  because
  this
  data
  will
  live
  in
  more
  than
  one
  location,
  fetches
  will
  become
  easier
  and
  faster.
  The
  upshot
  of
  this
  for
  the
  user
  will
  be
  a
  marked
  increase
  in
  computing
  speed
  and
  an
  overall
  boost
  in
  processing
  power.

• 
  AI
  everywhere:
  As
  artificial
  intelligence
  continues
  to
  make
  its
  profound
  presence
  felt—both
  in
  the
  computing
  industry
  and
  in
  our
  daily
  lives—it
  will
  have
  a
  direct
  influence
  on
  CPU
  design.
  As
  the
  future
  unfolds,
  expect
  to
  see
  an
  increasing
  integration
  of
  AI
  functionality
  directly
  into
  computer
  hardware.
  When
  this
  happens,
  we’ll
  experience
  AI
  processing
  that’s
  significantly
  more
  efficient.
  Further,
  users
  will
  notice
  an
  increase
  in
  processing
  speed
  and
  devices
  that
  will
  be
  able
  to
  make
  decisions
  independently
  in
  real
  time.
  While
  we
  wait
  for
  that
  hardware
  implementation
  to
  occur,
  chip
  manufacturer
  Cerebras
  has
  already
  unveiled
  a
  processor
  its
  makers
  claim
  to
  be
  the
  “fastest
  AI
  chip
  in
  the
  world”
  (link
  resides
  outside
  ibm.com).
  Its
  WSE-3
  chip
  can
  train
  AI
  models
  with
  as
  many
  as
  24
  trillion
  parameters.
  This
  mega-chip
  contains
  four
  trillion
  transistors,
  in
  addition
  to
  900,000
  cores.

CPUs
that
offer
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and
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Companies
expect
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lot
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In
turn,
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workloads
found
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data-intensive
business
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Organizations
need
workable
solutions
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change
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change.
Smart
computing
depends
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having
equipment
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capably
supports
your
mission,
even
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that
work
evolves.
IBM
servers
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strength
and
flexibility,
so
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concentrate
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the
job
at
hand.
Find
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IBM
servers
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