What I mean is say I have a dual core 3.2 GHz processor. Does that only run at 3.2 GHz or twice that at 6.4?

It runs at 3.2GHz, for each core. In other words, there's two 3.2GHz CPU's on a single die. The CPU package itself looks just like any other CPU, but there's actually two CPU's in there. When doing multiple tasks, a 3.2GHz dual-core CPU would actually perform better than a single 6.4GHz CPU. That's why dual-core is just so cool! :cool:

When doing multiple tasks, a 3.2GHz dual-core CPU would actually perform better than a single 6.4GHz CPU.

That of course presumes that you can get both cores working full tilt at the same time and that might be a wee bit hard to do, though not impossible. :D

I wonder how much it would take to max out one of those. . . :)

You need dual core "aware" 64-bit applications first. It'll be awhile...but it'll be here before you know it.

That of course presumes that you can get both cores working full tilt at the same timeNot necessarily. You can't just look at the numbers, you also have to look at the real time execution.

For instance, let's say you're typing a letter in Outlook Express when BAM! Your AV app fires up for a scheduled scan! Both of these types of programs aren't optimized for the newer CPU's (because they also have to run on the older ones), so they use just generic 32-bit ALU instructions. A 6.4GHz CPU would choke on this (on a clock-for-clock perspective) because the OS has to intervene and stagger the execution of these two programs so that neither one of them gets held up (which could kill the thread). So, 6.4GHz of power turns into about 2.13GHz of power per thread on average - one for Outlook, one for your AV app, and one for the OS (yes this is highly simplified). The result? Your system appears to "jerk" because Outlook is paused briefly while the AV app starts up and Windows intervenes to make sure Outlook doesn't crash.

On a dual-core CPU, this scenario is executed differently. Both Outlook and the AV app can co-exist peacefully on different cores. Because there's another 32-bit ALU available doing nothing, the AV app doesn't need to interfere with Outlook to start up and run, and less overall CPU cycles are wasted because Windows doesn't have to intervene so that nothing crashes. So you've got 3.2GHz of power for Outlook, and another 3.2GHz of power for your AV app. Windows needs nothing extra because it doesn't have to intervene. The result? The AV app fires up in the background on the second core while Outlook doesn't jerk, and you continue typing your email in bliss. :D

Dual-core has many such advantages in a regular computing environment, and a large part of the performance increase is based on this idea of less "jerking" because execution threads don't interfere with eachother, and so they don't have to be scheduled around each other. Do two chefs bake faster in one big kitchen or two smaller ones? ;)

Depends on how fat the chefs are. One big kitchen means more walking, so they get tired and slow down, maybe even run into each other and spill stuff all over the place, slip, fall, and break their necks. All cooking ceases--blue skillet of death.

All cooking ceases--blue skillet of death.Hahahaa! That's hilarious! Sounds like the title for a Bruce Lee movie! You could spin off a whole series!

Blue Skillet of Death Returns... The Revenge of the Blue Skillet of Death... The Forging of the Blue Skillet of Death (Mandarin title - Blue Skillet of Death: The Beginning)...

Hello saphalline, I liked that post you put up about how it won't jerk the app when a new one starts. Can you tell me where the literature is on that so I can know more? I am interested but don't know what to read. Maybe you can help me.

Now think of a dual core 64 bit processor!! That will be cool once one of those come into production!

Matt012,

The dual core Intel and AMD chips are 64-bit now. Yup...way cool.

Can you tell me where the literature is on that so I can know more?Here's a few links to get you started. They're a bit specific, but they give you an idea of what's going on when executing multi-threaded code in a supportive OS environment.

http://www.devx.com/Intel/Article/28617?trk=DXRSS_intelopt
http://blogs.msdn.com/rickbrew/archive/2004/12/28/339067.aspx
http://liberty.princeton.edu/Publications/cal05_dswp.pdf
http://www.iccd-conference.org/proceedings/2004/22310360.pdf
http://www.xbitlabs.com/articles/cpu/display/netburst-1_24.html

The first two links are just beginner's articles, and are nice and short. The third and fourth links are PDF files (from Princeton and Intel respectively) that talk about speculative exectution with multi-threading. Looking at the examples in those articles, you can tell right away that there's power to spare even in our current CPU's! If only the software engineers would catch up... The last link takes you to a massive article (on XbitLabs' website) about the P4's evolution. Page 24 specifically talks about similar thread execution in terms of Hyper-Threading performance, which is related in a hybrid sort of way to both single-core and dual-core execution of multiple threads.

In any case, these 5 links should give you a start and will introduce the many implications that come with code execution when resources run low.

I just happened to view this video on the Intel Extreme Edition dual core CPU. It's over at:

http://www.intel.com/products/processor/pentiumXE/index.htm

You just click on the Dual Core demo on the right side.

Awesome! You gotta love those rolling colored balls! ;)

I didn't think Intel had the 64-bit processors out yet, but I must be mistaken. What is the name of them?

The Pentium4 5x1 series and the 6xx series all have EM64T (Etended Memory 64-bit Technology) as well as the PentiumD 8xx series and Pentium Extreme Edition 8xx series. The Celeron D won't have it for quite awhile, and there are too many rumours floating around about the PentiumM to know for certain when that will get 64-bit support.

Meanwhile, AMD seems to be hitting the market hard with 64-bit support across the board. The Sempron now has 64-bit enabled in its core, so AMD is definitely banking on it. Intel seems content to push dual-core down everyone's throat. Both approaches are working. :D