On Sat, 18 Nov 2006 07:45:20 -0500, Neil Jones
wrote:
Hello,
I am seeing a lot of marketing of Dual Core systems. As you have
guessed, I am not a hardware geek. What is the big advantage of dual
core systems? I know it is like having 2 processors.
It's not just "like" having 2 processos, it IS having two processors.
Those two processors just happen to be on the same piece of silicon
(or two pieces of silicon packaged in one processor as in the case of
some Intel chips). The difference between having 2 processors on the
same silicon vs. two processors on the same physical processor chip
but on two separate silicon dies vs. two fully separate processors is
largely academic. Other than for determining how much money companies
like Microsoft, Oracle, IBM, etc. will charge for their software,
there really isn't much difference.
Will each core
perform at the high GigaHertz speeds that the marketers used in the past?
Err, mostly yes. If you look around now you will see that modern
processors are no longer sold according to the clock speed (ie
GigaHertz). Intel and AMD have both found that clock speed alone is
not a very accurate way of describing the performance of a processor.
As such they have both switched to a model name and number scheme for
their processors. For example, Intel's current chips are sold as
something like "Intel Core 2 Duo 6600" or "Intel Pentium D 950", while
AMD has their "AMD Athlon64 X2 4600+" or "AMD Opteron 2212".
The different model names and numbers combined will tell you the clock
speed, the type of processor core, the amount of cache as well as
whether they are single core, dual core or quad-core processors.
Occasionally other things get factored in as well, like bus speeds,
memory used or power consumption (power use has become rather
important in processors because it has skyrocketed in recent years.
Some of Intel's server chips consume more than 150 Watts in an area
not much bigger than a dime).
I plan to buy a new PC sometime early next year. Does the current
software technology take advantage of the dual core hardware? Is there
significant performance speed on the system?
Given that there are well over a million pieces of software out there,
that's a pretty broad question!
There are really two parts to that question. First is whether or not
the Operating System takes advantage of dual-core. The answer to that
is usually yes. Win2K, WinXP and Vista all do on the Microsoft side
of things, as do Linux and most of the BSDs. Windows 95, 98 and WinMe
do not and nor do a few of the obscure operating systems.
Now, OS support is important because all modern OSes are multitasking
systems. This means that OS can assign one task to one processor and
then stick another task on the second processor. This really is the
biggest and most immediate improvement from dual-core processors. The
computer is much better able to handle multiple tasks, and perhaps
most importantly, dual-core chips will give you a much more responsive
system.
Now, the second part of the question is the application side, and here
it's a bit trickier. You will often here the phrase "multithreaded"
thrown around here. This refers to an application that can split up
the work it's doing into 2 or more subtasks, or "threads". The
operating system can then send one thread to the first processor and
the second thread to the second processor, allowing both subtasks to
complete their work at the same time. Theoretically this could result
in an application doing things twice as fast if it can split the work
it does evenly between the two processors.
Unfortunately though, reality has to set in at some point. Splitting
tasks effectively between two workers is almost never 100% effective,
and sometimes isn't effective at all (just ask anyone who's tried to
manage two or more employees!). Some applications aren't written with
this in mind at all and others make only limited use of it. Others
still though do see HUGE improvements in dual-core systems. As such,
it's pretty much impossible to give a definitive answer to this.
In general, dual-core (and quad-core) chips are here to stay. They
are already the norm for servers, workstations and high-end desktops
and they are quickly moving down to the mid-range desktops and
laptops. They offer a BIG advantage right now in terms of
multitasking and responsiveness, while their impact on
single-application performance is growing. The retail price of AMD's
Athlon64 X2 line of dual-core processors now starts at about $150 for
the processor, which is pretty cheap. Full systems using this chip
start at about $600 and should be down under the $500 mark in about 6
months time.
Long story short: if you are buying a new computer, definitely get a
dual-core processor unless you absolutely can not afford one or have
some very specific need/reason not to.
----------------------------
Tony Hill
hilla underscore 20 at yahoo dot ca