Intel’s Sandy Bridge Family of Chips Core i3, Core i5, Core i7 , What’s the Difference ?

batteryfast.co.uk
October 18, 2011
Intel's Sandy Bridge Family of Chips Core
i3, Core i5, Core i7 , What's the Difference ?
Intel's Sandy Bridge Family of Chips Core
cores. The numbers are simply indicative of their
i3, Core i5, Core i7 , What's the Difference ?
relative processing powers.
We take a look at Intel's Sandy Bridge family of chips
Their relative levels of processing power are also
signified by their Intel Processor Star Ratings, which
Intel Core i3, Core i5, and Core i7 CPUs have been
are based on a collection of criteria involving their
around for over a year now, but some buyers still
number of cores, clockspeed (in GHz), size of cache,
get stumped whenever they attempt to build their
as well as some new Intel technologies like Turbo
own systems and are forced to choose among the
Boost and Hyper-Threading.
three. With the more recent Sandy Bridge archi-
tecture now on store shelves, we expect the latest
Core i3s are rated with three stars, i5s have four
wave of buyers to ask the same kind of questions.
stars, and i7s have five. If you're wondering why
the ratings start with three, well they actually don't.
What's the difference between an Intel
The entry-level Intel CPUs -- Celeron and Pentium
Core i3, i5 and i7?
-- get one and two stars respectively.
We take a look at Intel's Sandy Bridge family of chips
Note: Core processors can be grouped in terms of
their target devices, i.e., those for laptops and those
Core i3, Core i5, Core i7 -- the difference in a nutshell
for desktops. Each has its own specific characteris-
tics/specs. To avoid confusion, we'll focus on the
desktop variants. Note also that we'll be focusing
on the 2nd Generation (Sandy Bridge) Core CPUs.

See Also:

If
you want a plain and simple answer, then generally
Number of cores
print
joli speaking, Core i7s are better than Core i5s, which
are in turn better than Core i3s. Nope, Core i7 does
The more cores there are, the more tasks (known as
not have seven cores nor does Core i3 have three
threads) can be served at the same time. The lowest
number of cores can be found in Core i3 CPUs, i.e.,
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batteryfast.co.uk
October 18, 2011
Intel's Sandy Bridge Family of Chips Core i3, Core i5, Core i7 , What's the
Difference ?
which have only two cores. Currently, all Core i3s
For the Core i5-661, its maximum allowable proces-
are dual-core processors.
sor frequency is 3.6 GHz. Because none of the Core
i3 CPUs have Turbo Boost, the i5-661 can outrun
Currently all Core i5 processors, except for the i5-
them when it needs to. Because all Core i5 proces-
661, are quad cores in Australia. The Core i5-661
sors are equipped with the latest version of this
is only a dual-core processor with a clockspeed of
technology -- Turbo Boost 2.0 -- all of them can
3.33 GHz. Remember that all Core i3s are also dual
outrun any Core i3.
cores. Furthermore, the i3-560 is also 3.33GHz, yet
a lot cheaper. Sounds like it might be a better buy
Cache size
than the i5. What gives?
Whenever the CPU finds that it keeps on using the
At this point, I'd like to grab the opportunity to il-
same data over and over, it stores that data in its
lustrate how a number of factors affect the overall
cache. Cache is just like RAM, only faster -- because
processing power of a CPU and determine whether
it's built into the CPU itself. Both RAM and cache
it should be considered an i3, an i5, or an i7.
serve as holding areas for frequently used data.
Without them, the CPU would have to keep on rea-
Even if the i5-661 normally runs at the same clocks-
ding from the hard disk drive, which would take a
peed as Core i3-560, and even if they all have the
lot more time.
same number of cores, the i5-661 benefits from a
technology known as Turbo Boost.
Basically, RAM minimises interaction with the hard
disk, while cache minimises interaction with the
Intel Turbo Boost
RAM. Obviously, with a larger cache, more data can
be accessed quickly. All Core i3 processors have 3MB
of cache. All Core i5s, except again for the 661 (only
4MB), have 6MB of cache. Finally, all Core i7 CPUs
have 8MB of cache. This is clearly one reason why
an i7 outperforms an i5 -- and why an i5 outper-
forms an i3.
Hyper-Threading
Strictly speaking, only
one thread can be ser-
ved by one core at a
time. So if a CPU is a dual
core, then supposedly
The Intel Turbo Boost Technology allows a processor
only two threads can be
to dynamically increase its clockspeed whenever the
served simultaneously.
need arises. The maximum amount that Turbo Boost
However, Intel has in-
print
joli can raise clockspeed at any given time is dependent
troduced a technology
on the number of active cores, the estimated current
called
Hyper-Threa-
consumption, the estimated power consumption,
ding. This enables a single core to serve multiple
and the processor temperature.
threads.
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batteryfast.co.uk
October 18, 2011
Intel's Sandy Bridge Family of Chips Core i3, Core i5, Core i7 , What's the
Difference ?
For instance, a Core i3, which is only a dual core, can
Hopefully this gives you some insight for your next
actually serve two threads per core. In other words,
CPU selection.
a total of four threads can run simultaneously. Thus,
even if Core i5 processors are quad cores, since they
CloudTag: Intel's Sandy Bridge , chips , Core i3 , Core
don't support Hyper-Threading (again, except the
i5 , Core i7 , difference , Hp 510 batteries , Toshiba
i5-661) the number of threads they can serve at the
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same time is just about equal to those of their Core
i3 counterparts.

This is one of the many reasons why Core i7 pro-

cessors are the creme de la creme. Not only are they
quad cores, they also support Hyper-Threading.
Battery Technology, Laptop Battery FAQ, Technology
Thus, a total of eight threads can run on them at
Newschips, Core i3, Core i5, Core i7, Dell latitude
the same time. Combine that with 8MB of cache
d820 batteries, difference, Hp 510 Batteries, Intel's
and Intel Turbo Boost Technology, which all of them
Sandy Bridge, Toshiba pa3534u-1brs batteries
have, and you'll see what sets the Core i7 apart from
its siblings.
Did you enjoy this post? Why not leave a com-
ment below and continue the conversation, or
The upshot is that if you do a lot of things at the same
subscribe to my feed and get articles like this de-
time on your PC, then it might be worth forking out
livered automatically to your feed reader.
a bit more for an i5 or i7. However, if you use your
PC to check emails, do some banking, read the news,
and download a bit of music, you might be equally
served by the cheaper i3.
At DCA Computers, we regularly hear across the
sales counter, "I don't mind paying for a computer
that will last, which CPU should I buy?" The sales
tech invariably responds "Well that depends on what
you use your computer for." If it's the scenario des-
cribed above, we pretty much tell our customers to
save their money and buy an i3 or AMD dual core.
Another factor in this deliberation is that more and
more programs are being released with multithread
capability. That is they can use more than one CPU
thread to execute a single command. So things hap-
pen more quickly. Some photo editors and video
editing programs are multi-threaded, for example.
print
joli However, the Internet browser you use to access
Netbank or your email client is not, and is unlikely
to be in the foreseeable future.
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