Just what IS a QUAD core?

Grazie wrote on 11/21/2007, 9:37 AM
My apologies to start with here . . I thought I understood this . . but . . .

Is it a combination of Core2s?

Is it 2x core2 duos stuck together? Isn't it then like 8?!? What is the "duo" part anyway?

I've asked this and I am getting different or hazy replies.

Personally, I do NOT mind asking the dumb question. Hey, somebody else might benefit from the answer too.

TIA

Grazie


Comments

jrazz wrote on 11/21/2007, 9:43 AM
Grazie,

Some have two dual cores combined on a dye. Others actually have 4 seperate cores, each with its own l1 cache system. I believe that AMD gave Pentium a hard time b/c their cpu's where at first just two processors on one dye as opposed to a true multipcore processor.

Here is more on it.

j razz

4eyes wrote on 11/21/2007, 9:52 AM
I go by the Intel website:Whether it's encoding, rendering, editing, or streaming, make the most of your professional-grade multimedia applications with a PC powered by the Intel® Core™2 Quad processor. With four processing cores and up to 8MB of shared L2 cache¹ and up to 1066 MHz Front Side Bus, more intensive entertainment and more multitasking can bring a multimedia powerhouse to your house.
You can also use the comparison chart, notice amount of L2 Cache, FSB, speed stepping for overclocking
http://compare.intel.com/pcc/default.aspx?familyID=1&culture=en-US[/link

DrLumen wrote on 11/21/2007, 12:15 PM
Core2 is just a version name - as opposed to Core1. The duo means 2 processors. An intel quad is 2 duo's on a chip (2 dies @ 2 procs each). Some ppl are referring to them as 2x2's. The AMD's are putting their quad on a single die (4x1). They both have 4 processors.

Some will say the 4x1 is better but they will have more problems with quality as 1 or more procs may be bad on 1 core - hence the AMD tri. Theoretically the 4x1's should be faster but they will have more loss due to QC. The intel 2x2's are easier to make and have less QC issues.

What does this mean? The 4x1 MAY be faster eventually (not close to intel 2x2's yet) but they will cost more due to production QC losses. Whereas the intels are currently faster and should be cheaper.

intel i-4790k / Asus Z97 Pro / 32GB Crucial RAM / Nvidia GTX 560Ti / 500GB Samsung SSD / 256 GB Samsung SSD / 2-WDC 4TB Black HDD's / 2-WDC 1TB HDD's / 2-HP 23" Monitors / Various MIDI gear, controllers and audio interfaces

apit34356 wrote on 11/21/2007, 12:39 PM
Grazie, the 4x1 design is better than a 2x2. Even Intel has maded the jump to 4x1, but they did introduce 2x2 to beat AMD to the Quad market. The big reason why a 4x1 is better that a 2x2 is because of the memory management controller on the chip is design for 4 cores using local cache, vs, 2 core caches completing for memory cycles-------- basely, its a time sharing of cache management fighting over the memory controller, where the 2x2 design as an addition overhead of the separate two die chip completing for access while the 4x1 cache does does it in one cycle. Plus AMD has a better history of designing better performing cache controllers, than Intel; which played a big factor into Intel introducing a 2x2 chip earlier vs waiting for the 4x1, which was a good step for the consumer. As you have noticed, Intel is quickly removing the 2x2 design from the market to avoid comparisons to a 4x1 design. But the 2x2 was a good start for the general market and help push programmers to think "true multi-tasking" and real threads....
Grazie wrote on 11/21/2007, 3:13 PM
Well, thank you all! It wasn;t such a dumb question after all - huh?

So:

* A QUAD is 4 x 1cpu = 4 CPUs

* A Core2 is equivalent to ONE pair of CPUs = 2 x 1cpu

* A Core2 Duo is TWO pairs of CPUs = [2 x 1CPU] + [2 x 1CPU]

Hmmm.....

However it is the WAY these sets of CPUs are linked.

A QUAD has a 4 way integrated method of processing. They share their activity on a 4-way node setup.

A Core2 Duo has 2 PAIRS of CPUs that communicate with each other as/in PAIRS. Each PAIR has more power than a single. But then the processing is shared to the other pair AS a pair, on a 2-way node

Is that it?

Grazie
John_Cline wrote on 11/21/2007, 3:34 PM
In the Intel world...

A Core2 is a a single processor. i.e. Core2 Solo (1 CPU x 1)

A Core2 Duo is two processors. i.e. Core2 Duo (2 CPUs x 1)

A Core2 Quad is four processors. i.e. Core2 Quad (2 CPUs x 2)

There is also the Core2 Quad Extreme variant, which still has four processors. (2 CPUs x 2)
Harold Brown wrote on 11/21/2007, 4:10 PM
The real value of Quad is if the programs are written to take advantage of each core. Most programs are not using the CPUs as they could . It's like making breakfast. If you you do everything single threaded like make the eggs, then make the toast and then pour the juice it takes longer than if you made the toast and poured the juice while the eggs are cooking all while talking on the phone. Programmers have to write the code knowing how to allow for multi core CPUs otherwise everything is single threaded except for what the operating system can do.
The operating system just goes about its business switching from one program to the next so fast that everything looks like it is running at the same time. So when a program makes a call for input it hands that off, puts the program to sleep and wakes up another program. etc, etc
Grazie wrote on 11/22/2007, 12:58 AM
Harold, thanks for that and yes, I understand that.

John, you say "In the Intel world..." - why? Is there a difference with others. I'm assuming AMD? Yes? If so HOW different?

"A Core2 Quad is four processors. i.e. Core2 Quad (2 CPUs x 2)" Ah! So a QUAD is 2 of these Core2 (duos?) stuck together? OR does the Core2, when used in a QUAD configuration, become something OTHER than a duo? In this case a QUAD?

I think this has been my confusion.

John, thanks for your patience,

Grazie
John_Cline wrote on 11/22/2007, 1:10 AM
I was just speaking of Intel's naming conventions. "Core2" is an Intel registered tradename.
Harold Brown wrote on 11/22/2007, 10:05 AM
I want to buy an AMD Quad as my next machine. I have not started HD yet mostly because I am tired of being on the cutting edge. At this point in my life I want something that has stabilized out a bit. Thanks to all of the pioneers out there working through all of this.
The reason I like AMD is because Intel took two of their dual core CPUs and placed them together to get quad while AMD has four separate CPUs that work together. Designed as a quad from the ground up. Theoretically I would think AMD could reduce bottle necks but the proof is in the testing!
ushere wrote on 11/22/2007, 11:08 PM
first, thanks grazie for asking the question, and to those who gave such clear answers....

now, using v8a, and not attempting to multi task, etc., is the speed difference worth the cost vis a vis a c2d vs a quad?

i ask running a e6600 - which does me fine for p/b, preview etc., but some rendering times are now (even after my old 3.2 'eons') feeling like 'forever man!'

leslie
Grazie wrote on 11/22/2007, 11:54 PM
Leslie, no problem.

I just had a feeling I wasn't alone in understanding WHAT this means and thence WHAT the advantages/ramifications - good/bad/indifferent could be. And yes, your own experience is fundamentally reinforcing the reasoning, in the back of my mind, why I was asking the question too. What IS/ARE the the advantages? Now, there may very well be one or many, so let's hear them!

I'm not just asking this for the next best thing, or being a speed freak, or wanting to keep up with the Jones's. What I also want to know is what benefits AND necessity will there be for VPro"X"-64bit needing a QUAD?

Bottom line for me is that I have invested much MUCH time in Vegas. Why? 'cos I like the fundamental ( that word again!) philosophy of its interface AND that it is s/w driven not hardware driven ( mind you, faster PC is better than slower PC - isn;t THAT hardware driven . . moving on .. ), and implicit in this last comment is that the MORE powerful and faster a PC can run then I'm thinking the faster the actual Previewing of the timeline will be. And what do want good people? We want Real-Time Previewing! As PCs do become faster, Vegas, I would think, can only benefit. Yes?

So again, yes Leslie, render-times and why should they be lower? And what needs to happen? A QUAD+QUAD? An ability for Vegas to make use of even further/more CPUs? Is this what Madison are thinking? You'd hope so?

Intersting . . .

Grazie


(ps, my PC is going into hospital to get mended and . . upgraded!)


John_Cline wrote on 11/23/2007, 12:01 AM
You might want to check the "HDV Rendertest" thread and see what sort of render times people are getting in Vegas with various processors.

http://www.sonycreativesoftware.com/forums/ShowMessage.asp?MessageID=526098&Replies=123

At its stock clock speed of 2.66Ghz, my Intel QX6700 Quad core finishes the test in 117 seconds. Overclocked to 3.0 Ghz, it's 107 seconds and when seriously overclocked to 3.73Ghz, it renders in 85 seconds. My "every day" default clock speed has been 3.0Ghz, but I have run it for days at a time at 3.73Ghz will no apparent ill effects.

From looking at the HDV Rendertest thread, it has been reported that the 2.4Ghz E6600 renders it in 267 seconds.

John
Grazie wrote on 11/23/2007, 12:58 AM
Thanks John. I did read it.

How has your preview been? FX Previewing and so on?

Grazie