Single/Dualcore/Quadcore/Octacore and beyond question..

[xnox202]

I just had a talk with my fellow friend, and he went "Hey I got Q6600 @ 4Ghz, so I have 16Ghz each running, with 16Ghz processing power!"..

And I thought, "I don't think so? Doesn't it runs 1Ghz on each core?"

Same goes with Dualcore, lets say if a Dual Core processor runs @ 3Ghz, it means 1.5Ghz each on the core right? Regardless of the processing power thingy.. It is still 3Ghz?

I wanna clear this thing up once and for all, and I just can't find the right answers with Google.

 

[DrunkenMafia]

^ NO NO NO...

A 3 gig Dual core cpu will have 2 cores running at 3gig each. A quad core will have 4 cores running at the rated mhz etc.....

I have heard people refer to it before as having 4 times the processing power... so a 4 gig Q6600 could be reffered to as having 16gig of processing power.

I myself do not quite believe that as you still only have 1 FSB and 1 set of ram etc...

 

[Deleted member 3]

so a 4 gig Q6600 could be reffered to as having 16gig of processing power.

Couldn't be further from the truth, you cannot say it runs at 16GHz. Hertz is frequency, it's the amount of times the transistors switch per second. It is not a measure of performance or "processing power", therefor even if the performance doubles the clock does not change.

Imagine a train engine going 100MPH, adding another engine that runs at 100MPH doesn't make the train go 200MPH all of a sudden, together they still go 100MPH. However they would be able to pull more weight together, that's the performance.

 

[DrunkenMafia]

^ that is what I was sayin dan. "processing power" is a term I was using for "weight".... I know its not running at 16 gig. That is obvious. You simply have 4 times the "processing power" of 4gig... which I have heard it reffered to as 16gig (in this example) before....

But like I said I don't really believe it.

 

[hat]

No. If you have a quad-core CPU running at 4GHz it doesn't mean each core is running at 1GHz. It means each core is running at 4GHz. That said, having 4 cores at 4GHz doesn't mean you have 16GHz of processing power. You just have more cores which allows for more multitasking. Although if you happen to be running a multithreaded game like Crysis, having a 4GHz quad would benefit over having a 4GHz dual, that's where the performance comes in.

In other words he theoretically has 16GHz of processing power, but speaking theoretically isn't always speaking correctly.

 

[mullered07]

with a quad core @ 4ghz it gives you a "theoretical" processing power of 16ghz combined ie: if you had a program that could handle 4cores/threads and utilise each one 100% it would in "theory" be using 16ghz worth of combined processing power would it not

damn you hat you edited before i finished

 

[DrunkenMafia]

I give up.... lol

 

[hat]

with a quad core @ 4ghz it gives you a "theoretical" processing power of 16ghz combined ie: if you had a program that could handle 4cores/threads and utilise each one 100% it would in "theory" be using 16ghz worth of combined processing power would it not

damn you hat you edited before i finished

He does have 16GHz of processing power, but it's not like a singlethreaded game will benefit from having a dual-core cpu to a quad-core. If he had a multithreaded game like Crysis, he would be using all 16GHz of his total processing power. Although...

If he fires up 4 instances of F@H, each instance is only capable of using one core which would be 4GHz. So one program isn't getting all 16GHz but it is all being used. His WU's will still finish roughly all at the same time, but much like Dan's example since he's running 4 instances of that program he ultimately did 4x the work he would have with a single core 4GHz processor (provided it is based off the Core arcitecture )

@ xnox: He has a Q6600 right? As far as I know they come with a multi of 9x266MHz FSB which works out to roughly 2.4GHz (2394). So he is running 444x9 to get 4GHz right? That would mean his rated FSB changed to 1736MHz :O!!

 

[Wile E]

Regardless, it still doesn't give 16GHz of processing power, even if you did use a multi threaded app. These things don't scale at a 1:1 ratio, there are efficiency losses involved.

 

[mullered07]

Regardless, it still doesn't give 16GHz of processing power, even if you did use a multi threaded app. These things don't scale at a 1:1 ratio, there are efficiency losses involved.

hence why you have to tread careful and use "theoretical" and combined agreed a 16ghz single core would perform better than a 4ghz quad in a multithreaded game/app even if it was able to use all 4 cores

 

[hat]

Hm maybe a ratio of 1:1.00000000000000000000000000000000000000000000000000000000000000000000000000000000000000001

I don't see how it's possible to lose efficency like that?

 

[gR3iF]

There is Bandwith involved aswell.


Iam trying to get things down:

You have a Cpu its running with a certain frequency, then you have this cpu and its connection/ bandwith to the ram and the northbridge/ gpu.
These are factors that limits processing power:
To givbe a short example:

The first core2 Duo Pi Benches were done with 2 cores enabled and then Coolaler got his sub 10 Secs time.
Today normally one core is disabled and still were only sub 9 secs.

So if you have 2 Cores like Coolaler or one like some people today doesnt matter in a single thread application.


For Dual Core applications like Photoshop it doesnt work with double speed. The other limiting factors like Ram and Hdd are playing there role and so you get a nice boost but not 100% lets say maybe 70% boost is possible.

 

[Deleted member 3]

Like I said, frequency has nothing to do with processing power, it's just a specification. It's like the RPM of the trains engine, actual speed would for example be dependent on transition which would be the IPC. Either way, the train would never increase speed, no matter how many engines you add. Just as with the folding example, 4 WU's would be processed in the same amount of time, however it still takes the same amount of time to finish WU's, you can't process a WU 4x as fast. The 4 WU's that can be processed at once are the trains carts, each engine allows another cart to be pulled. (they're really heavy )

You can't add up frequencies, that's basically the point. No not even "in theory", your theory will be wrong. Adding up frequencies basically shows that you don't understand the matter.

 

[hat]

Indeed WU's are heavy.

 

[Wile E]

No, you can't literally add the frequencies. I can't speak for anyone else, but I'm speaking in theory, such that if you had 2 Identical systems, 1 with a 4GHz Quad, and one with a 16GHz Single core, both of the same architecture, if your were to assume no losses(which I know isn't the case), they would both have relatively the same abilities to process a multi thread capable app.

 

[Deleted member 3]

No, you can't literally add the frequencies. I can't speak for anyone else, but I'm speaking in theory, such that if you had 2 Identical systems, 1 with a 4GHz Quad, and one with a 16GHz Single core, both of the same architecture, if your were to assume no losses(which I know isn't the case), they would both have relatively the same abilities to process a multi thread capable app.

There is a lot of overhead in many things. So assuming "no losses" makes the whole theory rather meaningless. Also, the architecture might scale really bad at 16GHz or really good. There are so many variables, it's misleading to make such a comparison.

 

[Disparia]

And besides the hardware and architecture, there's the app itself.

"Multi-threaded app" is pretty general. In my hypothetical game: Salad Tosser Pro, I could have it where it only throws out one child process: life-like tomato physics. Everything else is handled in the main game loop. Multi-threaded? Yes, but scaling to >2 cores doesn't happen.

I could increase the threadiness of my app, but perfect scaling to multiple cores isn't going to happen. Example: Supreme Commander. In our hypothetical world, that 16Ghz SC is going to trump the 4Ghz QC. In the real world, that 16Ghz CPU could be a Netburst P4 with an increased pipeline

Bottom line: real products being tested with real software = worth a damn. Say, Supreme Command on an E6850 vs. Q6600.

 

[d44ve]

Couldn't be further from the truth, you cannot say it runs at 16GHz. Hertz is frequency, it's the amount of times the transistors switch per second. It is not a measure of performance or "processing power", therefor even if the performance doubles the clock does not change.

Imagine a train engine going 100MPH, adding another engine that runs at 100MPH doesn't make the train go 200MPH all of a sudden, together they still go 100MPH. However they would be able to pull more weight together, that's the performance.

I think this pretty much explains it.

I dont think I could think of an easier analogy

 

[Black Panther]

Forget about processor Ghz speed when talking about different processor types.

By analogy, a P4 is a car running at 100MPH carrying 4 persons (info)
A dual core is an MPV running at 100MPH carrying 8 persons.
A core 2 is a train running always at the same 100MPH carrying even more people
A quad core is a plane.... etc etc...

What you have to put into consideration is the MIPS (millions of instructions per second).
A P4 running at 3 Ghz would manage 8000 MIPS.
A C2D running at 3 Ghz would have 2 cores running at 3Ghz but would manage 24,000 MIPS ie more than twice a 'single-core' P4 running at 3Ghz.

 

[Deleted member 3]

Forget about processor Ghz speed when talking about different processor types.

By analogy, a P4 is a car running at 100MPH carrying 4 persons (info)
A dual core is an MPV running at 100MPH carrying 8 persons.
A core 2 is a train running always at the same 100MPH carrying even more people
A quad core is a plane.... etc etc...

What you have to put into consideration is the MIPS (millions of instructions per second).
A P4 running at 3 Ghz would manage 8000 MIPS.
A C2D running at 3 Ghz would have 2 cores running at 3Ghz but would manage 24,000 MIPS ie more than twice a 'single-core' P4 running at 3Ghz.

Yet nobody is talking about a P4. Just about the same architecture. ie a single core core2 at 3.2GHz vs a dual core at 1.6GHz.

 

[Black Panther]

Yet nobody is talking about a P4. Just about the same architecture. ie a single core core2 at 3.2GHz vs a dual core at 1.6GHz.

I know.

What one has to take into account is the millions of instructions per second (MIPS) that a processor is able to process.

A C2D, or quad-core... or octa-core or whatever will always be faster because it is capable of processing more MIPS per second when compared to a lower processor at the same speed.

On the same argument, it emerges out that the functions of a modern processor can't be compared to an old one. A 2.6 Ghz C2D will ALWAYS outperform a 3Ghz Celeron.

It's just a question of having the same vehicle transporting MORE information at the SAME speed.

Edit: Uh wait a second - a single core core2??? Well that means having a core 2 with a dead half... now I'm not that techie but I know that the technology of a core 2 would still surpass that of a single core even if half of that core 2 were dead.

Just know that from gaming experience.

For example Oblivion doesn't support multi-threading, neither does The Sims 2. That means on my un-oc'd processor it'd be running at 1.8 Ghz processor power. And it FAR outperforms the same processor power of the AMD at work which is single core.

 

[xnox202]

Looks like I've found the answers I've been looking for in this thread. Understood more. Thanks everyone!

 

[xnox202]

@ xnox: He has a Q6600 right? As far as I know they come with a multi of 9x266MHz FSB which works out to roughly 2.4GHz (2394). So he is running 444x9 to get 4GHz right? That would mean his rated FSB changed to 1736MHz :O!!

Well he said he recently got it, and went straight right oc-ing out of it. Haven't ask the details though. And I'm not too sure about Quad Intels, is that a heck of an O/C?

 

[bassmasta]

imagine the core is a road. some roads have one lane, some have two, your friend's has 4. the speed limit is 4 ghz. even if the car in each lane goes right to the speed limit, they are still only at the speed limit. so, you can have 4 cars reach their destination at the same time on that road, rather than having only one car reach it's destination at a time.

*** wasn't paying attention >.> didnt notice that he got it

 

[Wile E]

There is a lot of overhead in many things. So assuming "no losses" makes the whole theory rather meaningless. Also, the architecture might scale really bad at 16GHz or really good. There are so many variables, it's misleading to make such a comparison.

Right, which is why I said "in theory". I know perfectly well it's not the way these things work. It's more like a "what if" in that respect. Let me just make it clear that I do not believe a 4GHz quad in any way equals a 16GHz single core.