- Joined
- Jan 19, 2005
For those who haven't read the June MaximumPC, here's some interesting info about dual core cpus from Gordn Mah Hung. Excuse any spelling errors as I was typing this pretty fast. Was a good read for me and I broke it some if it down here. I also highlighted parts of interest in comparing AMD to Intel.
Is it anymore effective than Hyper Threading?
Hyperthreading is good until the cpu has to use the same resources for multiple programs. Like running 2 floating point intensive programs, there is no benefit at all over a non-HT cpu.
Example - Compressing digital audio to MP3 occupies floating point resources. Doing this while using a wordprocessing program or surfing the net is great.
Dualcores gives you two full cpu cores, letting you breeze through 2 floating point apps at once, something that would strangle an HT cpu.
Will it give double performance?
Not in the near future. The overwhemling majority of apps and games today arent optimized to exploit the advantages of dual core cpus. The program must spawn multiple threads that can be farmed out to each core. So don't expect a big boost in performance from your current DivX encoder or Unreal game.
Whats the difference between Intel's and AMD's dual core?
Penitum D is like a duplex house. It has 2 seperate cores integrated into a single cpu package. If you wanted to move a box from one closet to the other house's closet, you would have to walk out the front door (bus interface) of house 1, onto the sidewalk (front side bus), walk next door and through the front door of house 2 (bus interface).
In time, the cores should be able to communicate directly across the cores (like adding a doorway in the wall) and avoid using the slow FSB.
AMD uses a high speed cross bar interface to connect the cpu cores via the ondie memory controller. Unlike the PD cores, AMD's can communicate directly through this cross bar interface. Its like walking onto a shared porch to go next door, instead of using the sidewalk.
Why don't Intel and AMD just continue to make higher clocked single cores?
Both companies will continue to push their highest clocked chips to gamers and other people who dont give a damn about the benfits of multitasing. They both also realize that faster speeds consume more power and generate more hea, which offsets the benefits. The most public demonstration of thsi change in the philisoph occured last year, when Intel surprised the industry by killing its plans to introduce a 4ghz P4.
Theres no doubt the future lies in cpus with 2 cores or more.
Should I cate about dualcores if all I want to do is play games?
If all you want to do is game, the fastest single core cpu is the way to go; at least until more games are multithreaded. But if you ever want to transcode a video while simultaneously browsing the net or working Photoshop, dual core makes a lot of sense, especially since so many A-list games rely heavily on your video card. You make give up a few frames per second, but youll get a far more responsive PC in everything else you do.
What will be Intel's dual core specs?
They will have the Pentium D and the Pentium Extreme Edition. Both are based on 90nm tech, use 800mhz FSB and include 1MB L2 cache. The differences are that the PD will NOT have HyperThreading. It will show up in a machine as 2 cpus. The PEE, will have HT and show up as 4 cpus.
Why isnt the EE using the 1066mhz FSB? Intel says they cant use it on their dualcores on today's mobos without adding "electrical noise." In order to run, the mobos will require extra layers, which would increase manufacturing costs. They havent ruled out faster FSB in the future though, but its capped at 800mhz for now. Both cores are hooked up to the same FSB and can only communicate through that.
What will AMD have?
AMD's dual core will have 1MB L2 cahce per core with 2 independant cores based on the A64. But instead of being joined at the FSB, the cpus are hooked up to a "system request interface" which in turns hooks a crossbar switch plumbed into the on die memory controller. AMD says its design is far more elegant and suited to higher performance than Intel'stwo chips welded together design.
Which design is better?
Hard to say without field testing. According to Kevin Krewell, editor in chief of Microprocessor Report, AMD's design is clearly more sophisicated. Some industry observers have joked that when Intel makes dualcore procs, it just cuts apart every other die, instead of every die, as it does to produce a single core cpu.
On paper, AMDs dual core shows more sophisication through its use of the one die crossbar switch and system request. This design should lower the overhead inherent to multithreaded apps and render AMDs dualcore procs more efficient.
On the other hand, Krewell says, the Pentium D and the next gen 65nm Intel Presler cpu exhibit a simple elegance with their straightforward, if not primitive connection.
Eventually, multicore processors miht intermix their guts more and even share such crucial components as the cache. Shared cache in a multicore design would help when the two cores are working on the same data-think multithreraded apps-but it could hinder performance when the cpus are running two different tasks.
Why not just make dualcore chips as fast as the latest cpus?
Its entirely possible that running a dualcore proc at fullspeed could bring down the powergrid in your neighborhood. The single core 3.2 Prescott wasnt exactly a cool cpu, after all. Wile nearly doubling the size of the die didnt double the thermals-thanks to some power saving sleight of hand on Intel's part- they havent figured out a way short of liquid nitrogen cooling to jack up the clock speed to 3.8ghz without melting down your system.
Will they fit in my motherboard?
For AMD, if you own a Socket 939 mobo capable of running the FX55, you're good to go as long as the mobo maker creates a new BIOS to support it.
On an INTEL mobo, you're pretty much SOL. Despite conflicting hearsay from motherboard makers (and from Intel itself), the final word is that youll need a dualcore capable chipset to run the new chips-even though the dualcores are socket 775 processors.
What operating systems will run dualcores?
Microsoft as committed licensing Windows based on the number of cpus, not cores. This means if you have XP HOME, you're good to go. Numerous Linux distributions already support multiple processors via special symmetric multiprocessing versions of the kernal.
So will single core cpus hit a ceiling in terms of heat and power consumption?
Yes. Intel predicts that by 2008, consumer level cpus wll be able to handle 8 threads simultaenously. You can also count on Intel and AMD to add cache, increase clockspeeds, add special instructions and build entirely new architectures to increase performance.
Once apps are recompiled to fully utilize multi core cpus, consumers can expect to see phenomenal performance gains that will handily eclipse any boost youd get from from 200mhz speeds jumps or beefier cache sizes.
Ok thats about it. Hope it helped further educate some of you. Sure helped me a lot.
Is it anymore effective than Hyper Threading?
Hyperthreading is good until the cpu has to use the same resources for multiple programs. Like running 2 floating point intensive programs, there is no benefit at all over a non-HT cpu.
Example - Compressing digital audio to MP3 occupies floating point resources. Doing this while using a wordprocessing program or surfing the net is great.
Dualcores gives you two full cpu cores, letting you breeze through 2 floating point apps at once, something that would strangle an HT cpu.
Will it give double performance?
Not in the near future. The overwhemling majority of apps and games today arent optimized to exploit the advantages of dual core cpus. The program must spawn multiple threads that can be farmed out to each core. So don't expect a big boost in performance from your current DivX encoder or Unreal game.
Whats the difference between Intel's and AMD's dual core?
Penitum D is like a duplex house. It has 2 seperate cores integrated into a single cpu package. If you wanted to move a box from one closet to the other house's closet, you would have to walk out the front door (bus interface) of house 1, onto the sidewalk (front side bus), walk next door and through the front door of house 2 (bus interface).
In time, the cores should be able to communicate directly across the cores (like adding a doorway in the wall) and avoid using the slow FSB.
AMD uses a high speed cross bar interface to connect the cpu cores via the ondie memory controller. Unlike the PD cores, AMD's can communicate directly through this cross bar interface. Its like walking onto a shared porch to go next door, instead of using the sidewalk.
Why don't Intel and AMD just continue to make higher clocked single cores?
Both companies will continue to push their highest clocked chips to gamers and other people who dont give a damn about the benfits of multitasing. They both also realize that faster speeds consume more power and generate more hea, which offsets the benefits. The most public demonstration of thsi change in the philisoph occured last year, when Intel surprised the industry by killing its plans to introduce a 4ghz P4.
Theres no doubt the future lies in cpus with 2 cores or more.
Should I cate about dualcores if all I want to do is play games?
If all you want to do is game, the fastest single core cpu is the way to go; at least until more games are multithreaded. But if you ever want to transcode a video while simultaneously browsing the net or working Photoshop, dual core makes a lot of sense, especially since so many A-list games rely heavily on your video card. You make give up a few frames per second, but youll get a far more responsive PC in everything else you do.
What will be Intel's dual core specs?
They will have the Pentium D and the Pentium Extreme Edition. Both are based on 90nm tech, use 800mhz FSB and include 1MB L2 cache. The differences are that the PD will NOT have HyperThreading. It will show up in a machine as 2 cpus. The PEE, will have HT and show up as 4 cpus.
Why isnt the EE using the 1066mhz FSB? Intel says they cant use it on their dualcores on today's mobos without adding "electrical noise." In order to run, the mobos will require extra layers, which would increase manufacturing costs. They havent ruled out faster FSB in the future though, but its capped at 800mhz for now. Both cores are hooked up to the same FSB and can only communicate through that.
What will AMD have?
AMD's dual core will have 1MB L2 cahce per core with 2 independant cores based on the A64. But instead of being joined at the FSB, the cpus are hooked up to a "system request interface" which in turns hooks a crossbar switch plumbed into the on die memory controller. AMD says its design is far more elegant and suited to higher performance than Intel'stwo chips welded together design.
Which design is better?
Hard to say without field testing. According to Kevin Krewell, editor in chief of Microprocessor Report, AMD's design is clearly more sophisicated. Some industry observers have joked that when Intel makes dualcore procs, it just cuts apart every other die, instead of every die, as it does to produce a single core cpu.
On paper, AMDs dual core shows more sophisication through its use of the one die crossbar switch and system request. This design should lower the overhead inherent to multithreaded apps and render AMDs dualcore procs more efficient.
On the other hand, Krewell says, the Pentium D and the next gen 65nm Intel Presler cpu exhibit a simple elegance with their straightforward, if not primitive connection.
Eventually, multicore processors miht intermix their guts more and even share such crucial components as the cache. Shared cache in a multicore design would help when the two cores are working on the same data-think multithreraded apps-but it could hinder performance when the cpus are running two different tasks.
Why not just make dualcore chips as fast as the latest cpus?
Its entirely possible that running a dualcore proc at fullspeed could bring down the powergrid in your neighborhood. The single core 3.2 Prescott wasnt exactly a cool cpu, after all. Wile nearly doubling the size of the die didnt double the thermals-thanks to some power saving sleight of hand on Intel's part- they havent figured out a way short of liquid nitrogen cooling to jack up the clock speed to 3.8ghz without melting down your system.
Will they fit in my motherboard?
For AMD, if you own a Socket 939 mobo capable of running the FX55, you're good to go as long as the mobo maker creates a new BIOS to support it.
On an INTEL mobo, you're pretty much SOL. Despite conflicting hearsay from motherboard makers (and from Intel itself), the final word is that youll need a dualcore capable chipset to run the new chips-even though the dualcores are socket 775 processors.
What operating systems will run dualcores?
Microsoft as committed licensing Windows based on the number of cpus, not cores. This means if you have XP HOME, you're good to go. Numerous Linux distributions already support multiple processors via special symmetric multiprocessing versions of the kernal.
So will single core cpus hit a ceiling in terms of heat and power consumption?
Yes. Intel predicts that by 2008, consumer level cpus wll be able to handle 8 threads simultaenously. You can also count on Intel and AMD to add cache, increase clockspeeds, add special instructions and build entirely new architectures to increase performance.
Once apps are recompiled to fully utilize multi core cpus, consumers can expect to see phenomenal performance gains that will handily eclipse any boost youd get from from 200mhz speeds jumps or beefier cache sizes.
Ok thats about it. Hope it helped further educate some of you. Sure helped me a lot.
