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Dual Core

by sicky nar-nar / May 15, 2006 11:43 AM PDT

if i get a dual core processor that says it's 2.0 GHz then do i have two 2.0 Ghz processors making a 4.0Ghz computer or do both processors together get me 2.0 Ghz. if the latter, wouldnt it be faster to get a single core 3.0Ghz processor than a 2.0Ghz dual core processor?

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Let's put it this way
by PKsteven / May 15, 2006 2:57 PM PDT
In reply to: Dual Core

The dual core is what it is, two. The speed is a relative term here because of two, it was supposed to access other chips and memory faster, two people shoveling as opposed to one. Does it mean two people are shoveling any faster than the one person? No, but the job gets done faster. Typically this is not doubling cpu speed but having better flow. Look at it this way, for high end programs like Adobe Photoshop, or games, you will see a difference due to both cores working as opposed to one trying to pump information through. It may perform better, a bit faster than single core, but still not near a true multiple cpu setup.
So no, you don't get 4.0 out of a 2.0 cpu. Hope this helps, Paul

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True multiple CPU.. means..??
by akhilneo / May 18, 2006 6:37 PM PDT
In reply to: Let's put it this way

Thanks for the clarification on this point, comicfan, but I gotta ask what your parting comment meant - are you implying that the current dual-core processors are NOT equivalent of, say a server MB with multiple processors on it? Plain

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Duo-Core Processing (Doubling its Speed?!)
by fixitphil / May 19, 2006 1:00 AM PDT


I agree with "Comicfan". Duo-core just means that. Whatever the chip speed (for sake of discussion, let's say 3.0) The speed on this cpu is constant. But the tasking or processing power is doubled or shared by the other cpu. It's like having a partner help you complete a task that normally take twice the time.

There are motherboards out there now that can have the capability of having (4) processors installed! Just think of the processing power you can have with (7) additional hands helping you complete a task!

I hope this helps...

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multiple processor machine
by KatieMarieGlenn / May 19, 2006 5:04 AM PDT

There machines out there that can have many more than 4 processors. I opened up a computer that was probably about 3-4 years old last week and found it had 5 CPUs. I think the big difference between having multiple processors and having dual core processors is that like you said in your example of multiple workers. You can do twice as much work at the same time, but with dual core, there's still only one pipe. All information coming in and out of the processor will be going through the same bus. I'd also wonder whether a dual core processor has doubles of all the registers. Most likely not. Registers are like small bits of memory contained within a processor. The processor can only make calculations and deal with data within theses regeisters. So data comes in from memory, gets put onto the registers, makes the calculations, and returns the appropriate information. With dual proceessors there'd certainly be two sets of all registers, but I'd venture to guess that this wouldn't be true with a dual core processor.

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Duo-Core Processing / Now Memory!
by fixitphil / May 19, 2006 8:10 AM PDT

The amount of memory you have on the mother board is another issue! Memory cache comes into play also in processing. So there are alot of variables that come into play here when you configure a system to do specific job! It doesn't stop at processing power but the combination of all factors.

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There is a saying...
by PKsteven / May 21, 2006 5:18 AM PDT

Your pc is only as fast as your memory.


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That's a terrible saying and is incorrect
by Ray Harinec / December 3, 2006 9:01 AM PST
In reply to: There is a saying...

The architecture of the chip can make far more difference. Simply read about the Intel Conroe cores.

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2 plus 2 does not equal 4 here.
by Paul C / May 15, 2006 7:54 PM PDT
In reply to: Dual Core

A dual core processor is a processor that, as its name implies, has two identical cores running at the same clock speed (in this case, 2.0 GHz.

As Comicfan said, it does NOT necessarily run everything twice as fast. That's because most programs are not written to take advantage of this feature - although I expect that will change in the future.

When used with certain tasks (Comicfan mentioned Photoshop; also include video work and some graphics and game programs to that list), a dual core proc will have a noticeable speed advantage. You may also notice speedier performance in many a multitasking situation, although the speed boost there won't be as great.

All that said, I'd still go for a dual core proc; as I noted above, we'll start seeing more software written or rewritten to take advantage of this hardware.

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About the speed of dual core processor
by imaudi / May 19, 2006 7:36 AM PDT

He has explained it in a nutshell. Unless software written for dual core processor are available, till then the processor is a show piece only except for programmes like Adobephotoshop, 3dMAX, Maya and gaming.

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?? 3.0 Ghz Dualcore = 6.0 Ghz potential ??
by davejramos / December 13, 2009 7:05 AM PST

If a program was perfectly written to take advantage of a dualcore processor (say 3.0 Ghz), would it then theoretically be operating near 6.0 Ghz?


theoretically, are there simply limts (ie: FSB, Cache,...) that essentially block a dualcore processor from ever completely doubling in processing power?

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by rick550 / May 18, 2006 7:07 PM PDT
In reply to: Dual Core

if the program you are using is multithreaded, then it would be faster compared to a 3 GHz processor of the same type. if its single threaded, then it would most likely be slower. the cool thing about dual core processors is that they multitask very well. even with Intels hyperthreading, multithreaded applications work better, but a dual core processor is the way to go.

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by 3rdalbum / May 18, 2006 8:53 PM PDT
In reply to: no

You may see an improvement with single-threaded programs too. Half of the programs may be executing basically in one core, and the other half in the other core.

However, Symetrical Multi Processing (dual-core and dual-processor) only works with Windows XP Pro or the Linux SMP kernel. However, if you buy a dual-core computer it's highly likely that XP Pro will come with it, and if you run Linux you can install the SMP kernel from your distribution's repositories.

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You forgot to add Mac/OS X to the list
by gatechhusker / May 18, 2006 10:45 PM PDT
In reply to: Also...

The Mac OS X (10.4.x) also does SMP.

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Re: dual core only working with MS pro?
by willr / May 19, 2006 8:20 AM PDT
In reply to: Also...

If I read correctly you say a dual core processer will only work on MS Pro ,Linux and MacOSX. I have been looking at new dualcore laptops as I do very heavy tasks (like video editing, photoshop). The laptops I am looking at buying have dual core processers but one runs MS Media Edition and the other runs MS Home. Does this mean I will not see the full affects of the dual-core cpu??

Also as a side note, will a 1.66ghz Intel CoreDuo give me the power to run things like photoshop and video editing? would it be better if I paid the extra $280 for a 2.0ghz Intel CoreDuo?


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(NT) (NT) What advantage with dualcore ?
by the2jsofsin / May 18, 2006 10:00 PM PDT
In reply to: Dual Core
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by shaniroze / May 18, 2006 10:48 PM PDT

There are several advantages that can be immediately seen.
First, when running multiple applications that use a lot of CPU time (such as doing a recalc on a large spreadsheet or running an intensive filter in Photoshop), an entire application thread may be shunted to its own processor leaving the other processor for more immediate or mundane work.

With the fear of sounding like a commercial:
If your CoreDuo processor happens to be in an Apple Macintosh computer running the Parallels virtual environment, you might find Windows XP Pro (SP2) running on one processor while Mac OS X (Tiger) is doing its work on the primary processor. In such a setup Windows XP runs as just another application in a window of Mac OS X and the Mac OS when, how and where each app, thread or operation is performed on which core. In short, you can run Macintosh X and Windows XP applications at the same time, on the same machine, on the same or dual screens. I've done this on my Intel-based Apple MacMini CoreDuo running Parallels and a Sony display.

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What do you want out of your computer?
by Nargg / May 18, 2006 11:10 PM PDT
In reply to: Dual Core

It's a question of what will you be running on your computer. If you are a multitasker by nature, in other words run many multiple programs at once in normal day to day work/play. (a lot of programs could mean a lot of things like an IM program plus a game, or another system management tool and web browser and word processor etc etc.) Then you'd gain a LOT of multiple core processors.

On average a dual core or dual processor will gain you about 40% more speed overall. Usually no more than 80% increase on speed depending what applicaitons you are running. Sometime you may even see a decrease on some apps if they are not written well. The OS has a lot of housekeeping with more than one processor, which is the reason for the whole system not getting a true 200% boost.

My favorite example of the good and bad is when John Carmack of ID Software (Doom, Quake, etc.) wrote that in attempts to get more speed, was unable to due to the overhead of house keeping the two processors. It took more work to keep all the data flow in sync than could be added to the speed of the entire application, or game in this case. More recent attempts have been better as the OSes and the applications are getting better written to handle multiple processors with less overhead. There are a lot of web sites with information on the good and bad of dual procs. is one I like.

Hope that helps.

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Good for encoding
by erci0116 / May 19, 2006 12:30 AM PDT

I have found that media encoding (music, movies, video) really get a boost from dual processors. Even those processes that are single threaded seem to perform better because the OS can put system and other threads to the second processor, freeing the first processor to really work. I use MusicMatch's Suppertagging and it would routinely crash a single core Pentium M computer because the OS would not have resources to run OS threads. On my Pentium D 3.2GHz, it still maxes out the first processor, but the second is free to run other threads and leaves Windows very responsive. My opinion, dual-core is what a true multitasker needs.

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Dual Core
by garfent / May 19, 2006 3:54 AM PDT

I can't talk about the technical aspects, but I know this. In all my upgrading from the 286-386-486-Pentium 1-2-3-4, I never was very impressed with the difference between them. I'm sure if I had gone from the 286 to the Pentium 4 I would have noticed. But between individual upgrades I was always disappointed in the result.
Then I got what I have now. An AMD 64 X2(dual core) 4200. My last Pentium ran at 2mhz. This one runs at 2.2. So It's not the increase in the clock rate I'm seeing.
The minute I stated using it, the difference was striking. I understand that technically it doesn't run any ''faster'', but I'll tell you, it sure does seem to!
The only downside I've found (and it's really not a big deal) is that some games don't like the dual core. Specifically Serious Sam 2, Painkiller, among some others, I couldn't get to run properly, or at all, until I set the Windows 98 compatibility setting. problem. I think that sets it to run with one core, among other things. But like I said, it's not a big deal, and the increase in productivity outweighs that by a huge margin. I'm very happy with mine.

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dual core like other dual systems
by acoxon1274 / May 20, 2006 3:31 AM PDT
In reply to: Dual Core

If the software companies can setup so the dual cores work together then dual core could be almost as fast as a single core with duoble the speed of one of the dual cores. My problem with this statement is that it is a big IF.

Dual core will be faster under some usages but not by double. The dual core processor is a way around heat problems. As the speed of processors has gone up the number of transistors inside the processor has gone up and that means more energy to run them and that means more heat to take away. So the chipheads came up with dual core as a work around, it is a stop-gap-measure, which may or may not be a solution. Let's wait and see.

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Why it is almost always better; duel core
by cayble / May 20, 2006 4:18 AM PDT
In reply to: Dual Core

The significant advantage of a duel core processor is its ability to divide up the work it is doing between two CPU cores as opposed to ding it all through a single core. The reason why this is an advantage lies in the fact that most computer processes require nothing like 3.0gigs of processing speed to function well on their own. The extra power becomes useful when you have more then one thing on the go, which is often the case for most people.
Take a simple example of someone doing some work on documents on their computer at home. If the computer is on the internet, and lets say the person has some background music playing on the computers media player, perhaps they have Messenger open as well so they are open for messaging online and they may have a couple of Word documents open along with a pdf file or two and suddenly you can see that there are a lot of things running through the CPU?s brain all at once so to speak. While even all this is not likely to press a 3.0gig single core too hard, you still have to rely on all the resources in that one core to handle the entire workload all at the same time, and the result is that there will be those occasions where you are attempting to draw on the exact same resources of that single core at the same moment with two different applications and you have to rely on the high speed of the single core to quickly move things in and out so the delays, or lag are minimal.
With a duel core processor the workload can be channeled between the two cores effectively reducing the likelihood, often significantly, that there will be any lag between operations due to multiple applications trying to get access to the resources of a single core at the same time. Of course this difference is typically less and less noticeable if you compare a very fast single core; say a 3.6gig, to a slower 2.66gig duel core the difference is gone. In fact, for a single running application, such as a game, a very fast single core CPU is likely to yield superior results then a slower duel core. It?s the duel cores ability to spread its speed out across the two brains of the CPU if you will, that causes less confusion in the CPU and tends to make more applications really ?snap? into play when you have more then one thing on the go.

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Twice the resources, not twice the speed
by jiwhite / May 20, 2006 6:44 AM PDT
In reply to: Dual Core

Havaing a dual core processor is like having two people to do a job instead of one. The people work ata the same speed they always work, but the job gets done twice as fast if both people can contribute to the original job at the same rate. When you have a dual core processor, the computer will finish whatever task you give it twice as fast if the job can be split up into tasks that both processors can work on at the same time. Some programs have been optimized to work this way, so a dual core processor will finish the task twice as fast as a single core processor, but many have not. Although you are getting essentially two 200 Ghz processors from a dual core processor, you won't always finish a task twice as quickly as a single 200 Ghz processor.

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All the hype
by PKsteven / May 21, 2006 6:04 AM PDT
In reply to: Dual Core

As you have read, there is a lot of hype associated with this. Let me say this, my son was playing music videos\had 4 messenger windows open\surfing the web\using gimp\and still managed fine. This is on a 32 bit single core 1.2 AMD, only 512 ram with a bit of noticable slowdown, had I had 1 gig ram, no problem at all. How many will you be running?

You will not see an improvment with an application not written for 64, the number of apps, yes. Dual is NOT faster, simply as I stated, flow is better, remember the shoveling?

It's the typical kid in a candy store scenario. Wow! 64! It's better! Faster! gotta have it! I know many guys who have recently bought, built, 64 bits. Except for the gamers "who had problems running games on them" said they wasted their money. They didn't realize they wouldn't need the dual core power. A few liked them but It simply wasn't what they expected.

Now simply look at this, will you be running high end graphics and other high end applications\ and many of them?

Do you think you will need this for the future of graphics\video\games whatever?

Is it going to be a great benefit? Will you be ahead of the game?

Do you go with a cheaper 32 bit until a possible 2 to 3 years when 64 is most likely going to be needed by most apps? The outlook for having all new 64 bit apps is around two years or more. "Although that is anyone's guess." and not mine.

But in the end, it's up to you. To be honest , I am going to build a 64 but plan on working with high end graphics and videos in the near future. So, in my case it will benefit. If I wasn't going to be working with 3-d graphics\videos, then NO, I wouldn't bother to be honest.


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Yes, Just say no to the HYPE
by acoxon1274 / May 22, 2006 9:55 AM PDT
In reply to: All the hype

I bought into hottest PC in 1998 and paid $3,000.00 and most of its bells and whistles were never fully used.

I still run win98se and still don't run XP. I got on the hype wagon with ME thinking it would be supported for along time. I never installed it because of all the problems with it. Win98 and ME support are to end June this year. ME dies with 98, NUTS.

The HYPE wagon is not a ride I want to take again.

Dual core maybe a good thing but I will wait. My hope is that the anti-virus companies will setup a anti-virus program that will run on one of the dual cores and that all other programing companies will write programs for the other core.

I guess the old advice is still good. ''Buy the computer that will run the software you want to use.''

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Just like a 2-cpu system.
by simpleways / May 23, 2006 1:35 AM PDT
In reply to: Dual Core

Multi-core CPUs are (supposed to be) a slightly better-integrated and cheaper to produce implementation of a multi-CPU system. The issue here as with every other multi-CPU setup is scaling and how the apps are coded.

The easy one to explain is how the apps are coded... A single-thread, single process program can only run on one CPU at a time. The only advantage you get from multiple CPUs or cores here is that all the other stuff the OS is doing in the background doesn't get in its way. When you get into multiple processes or parallel threads within a single process then provided the OS is intelligent enough to share the load across all the CPUs properly the speed increase will be much more noticeable. This is easier to do when the app splits its work across multiple processes than multiple threads. Pretty much any multi-CPU aware OS can do it with processes but you need a fairly recent one to properly parallelise threads across multiple CPUs or cores and some will only do it if the apps programmer takes that possibility into account.

Scaling is a measure of how much extra performance you get from an extra CPU or core and is almost never a direct relationship - by doubling CPUs you never get twice the horsepower. The OS has to do more work to balance the load across the CPUs and cores and that extra comes out of your potential performance boost. The "holy grail" here is to achieve what they call "linear scaling" but nobody can manage that. Typically CISC processors like those found in PCs start to hit diminishing returns above 4 CPUs or cores - beyond this number the performance increase you get from extra CPUs is so close to the performance hit you take from the increased overhead that it isnt worth the expense. Some RISC chips have historically been better at scaling.

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2 Horses One Cart
by dog2 / May 31, 2006 5:55 PM PDT
In reply to: Dual Core

In simple words: Two 2.0 GHZ processors on a board are just like two horses (with equal speeds and powers) in one cart.
Assume each of the two horses can pull a empty cart at a speed of 2 meter per second individually.
Now when you make both horses to pull the same cart, they can't exceed the speed of 2 meter per second as they can't run faster than it.

Then What is the advantage of dual processor on a board?

When you increse the load on the cart, two horses can carry the load at a better speed than a single horse. More the load on the cart, more the difference will be visible between performance of "single horse" cart and "dual horse" cart.

Technically: Regarding 2 dual core 2.0 GHz processors on one board compared to One 3.0 GHz Processor.

Certainly 3.0 GHz will perform better than two 2.0 GHz in almost all the tasks due to the 50% more processing speed.

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processor help
by jstrnck / December 3, 2006 4:57 AM PST
In reply to: 2 Horses One Cart

ok, let ask this-i need a new comp- i just got an compaq AMD 3500 and its horrible- my compaq celeron 340D is much better but cant handle my task (even with 1GB memory)- im not on the internet while running this and turned off everything i can think of-- i process AVI,s in registax (stacking program) each AVI to run as large as 400MB- so im not 'multitasking'-- i dont care about having other programs open or playing music or anthing- i just want a platform that can handle large AVI files for processing- so would a duo-core benefit me-- or a better processor like a pentium 4 with 'XT' technology or whatever its called- thx- john

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Just a guess...
by steve749 / December 3, 2006 6:01 AM PST
In reply to: processor help

With a program using 400 MB this is generally large compared to the cache on most processors which now run about as high as 4MB so there will likely be lots of swapping going on between the CPU and the RAM. While a dual-core would be better than a Pentium 4 with "HT" technology which simulates dual-core there is still the issue of the cache for which I would offer the suggestion of looking at server systems rather than workstations which are generally not that beefy.

Another point is that if what you are working with can be as large as 400 MB then it may be worth looking at getting more memory to help give some more elbow room on things.


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by jstrnck / December 3, 2006 7:58 AM PST
In reply to: Just a guess...

ok thx for the info, let me ask you this then- i take the frames from a webcam- i might capture 10FSP @ 90 seconds- so i have 900 frames i save as an AVI- which gives about 700-800MB size file- then i open registax and the AVI for stacking-- sorta like opening opening 900 JPG,s in photoshop at one time-- the program runs smoothly aligning the images- but when i start into the stacking process- the program speed runs outa gas-- so what you do if (or get) if you going to do someting like this?- ram? new CPU? etc- thx, john

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by steve749 / December 3, 2006 9:48 AM PST
In reply to: response

Generally a little digging is done at this point to see if there are memory issues or if it is all in the processor or if it is somewhere else, e.g. video card, where the bottleneck is. One idea is to run "Task Manager" just before you open registax and then open registax and see what happens in terms of CPU usage and memory as well as noting if the physical memory runs low which could be a sign of needing more memory while if the CPU seems to be heavily used then it may be worth seeing if a server CPU, e.g. Xeon or Operton, may be worth using instead of a desktop CPU.


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