Also now on Icrontic: Quad Core Processing
The latest buzz in the processor industry is about dual core processors. AMD may be the first to take the limelight with their announcement of dual core AMD Opteron processors set to launch in mid-2005 but Intel and IBM are cueing up their dual core processors as well.
A dual core processor is exactly what it sounds like. It is two processor cores on one die essentially like having a dual processor system in one processor. AMD's Opteron processor has been dual processor capable since its inception. Opteron was designed with an extra HyperTransport link. The relevance of it was mostly overlooked. HyperTransport Technology simply means a faster connection that is able to transfer more data between two chips. This does not mean that the chip itself is faster. It means that the capability exists via the HyperTransport pathway for one chip to "talk" to another chip or device at a faster speed and with greater data throughput.
We knew that HyperTransport Technology would provide for a faster connection to system memory, the GPU and the rest of the motherboard but back in the fall of 2003 we thought of the extra HyperTransport link as a connection to another physical processor.
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It didn't dawn on us that the "extra" processor could be on the same die. While some will say "I knew that" most didn't pick up on it.
AMD have the added punch of being able to drop their dual core Opteron processors into existing 940-pin sockets. This upgrade path is extremely favorable as all it will require is a processor swap and, perhaps, a BIOS update.
Intel are continuing with their Pentium 4 cores by releasing two flavors codenamed Paxville and Dempsey. The codenames will very likely change once the marketing department gets their hands on it as "Introducing the new Dempsey" has a very lackluster ring to it.
MAC orientated Think Secret posted IBM plans on the PowerPC 970MP codenamed Antares and rumored to clock in at 3GHz with a 1GHz EI (Elastic Interface) bus.
The horses are now in the paddock. AMD, INTEL and MAC loyalists are beginning to group at the fence to eye up their favorite and the competition. The post parade is still a ways off and with post time now set at mid-2005 it's anybody's guess who will be out of the gate first.
Why dual core?
Why the shift to dual core and how will this impact the gigahertz performance race? Who or what will dual core processing benefit and will it be sought after by enthusiasts or left buried deep inside the dark recesses of server rooms?
The broad brush paints a processor as a device that executes a series of instructions to tell it what to do which, in turn, tells everything else it interacts with what to do. The faster it can do this the better. "Faster" can be directly related to clock speed but don't make the mistake of thinking that INTEL's higher clock speeds make it "faster" than AMD.
Both AMD and INTEL scaled up the clock speeds of their processors in a very short amount of time but have recently slowed the curve. AMD moved from the 1GHz "Thunderbird" to the Athlon64 FX53 in In a little less than 4 years which is impressive considering from 1997 until 2000 the K6 processor family saw a mere 4-500 MHz clock speed increase.
It is the flattening of the clock speed curve that some are reasoning why a shift to dual core. Some have surmised that AMD and INTEL have hit clock speed walls and another route is being taken to continue the performance curve and stay top of mind with new product releases. The problem with winding up clock speeds is heat. At present the processor engine can operate at only so much RPM before the engine will seize. Heat is the enemy of any processor and high clock speeds mean high heat and that means errors. A Windows PC running at 10GHz isn't much good if it can't make it past booting up before crashing.
That heat comes from power. It takes a lot of juice to crank up a processor to high clock speeds and a processor with that much electricity running around the die is prone to noise. It's not audible noise like a high RPM cooling fan but electrical noise otherwise akin to interference. The pathways on a processor are microscopically close together. The more power that runs through these pathways due to the requirement of higher clock speeds means that there will be a small amount of electrical radiation from one pathway to the next. That leakage could corrupt the data in another pathway. Corrupted data means errors which means a program could get cranky.
Think of it like a hot element on a stove. A hand can be placed fairly close with the burner on low. Turn the burner up to high and it get's pretty uncomfortable to keep a hand at the same distance it was when the burner was on low. It may even burn a hand. The radiated heat from the burner "corrupts" the hand resulting in a burn. In a processor the thermal heat is an issue but it's also the electrical noise like a radio station that isn't quite tuned in. The data is "dirty" and the song isn't clear enough to understand.
gimme gimme gimme
MediaMan, i would like to give my most sincere thanks for an absolutely fantastic article. Me and a few of my friends here at Shell ( UK ) are really interested in the upcoming dual core technology. The difference between you and other reviewers is that you explained things so smoothly.
Many thanks.
James.
I love the gimme icon
James,
Thank you for the comment. I hope you keep poking about our site.
Interpreting the crystal ball on this technology is one part science and one part darts. My crystal ball sees dual core as indeed a performance increase. That's a given with any new processor product at the top of its line.
When you look at it from a consumer cost point of view it begins to make a bit of sense. It's ideal for workstation users who have a desire for a bit more "horsepower" than a single processor system but don't have/want to spend more $ for a dual processor system.
Dual core brings some of the benefits of a dual processor system at less than the cost of a 2P system with the two of the same processor equivalents.
Remember that it's not so much about flat out dragstrip speed anymore. A dragster isn't much good at towing your boat down the highway. It's more about having that big truck with the towing power...that can keep up with the dragster or at least give it a good run for its money.
For server environments it's the same way of thinking. Many run dual processor servers but would really like a 4P server to really go to town. But then there's that cost factor. A dual core system can bump them up between a 2P and 4P system for some aspects of performance (increased multitasking) but without that cost.
For those with oodles of money? Imagine a 4P or an 8P system with dual core processors...that would translate up to a psuedo 8P or 16P system. Interesting if anyone tries to make an 8P dual core system actually work...just for the heck of it.
Bottom line dual core isn't exactly the same as a two physical processor system but it's better at some things than a single processor system. On launch this is more a product for working rather than playing...
In time...it'll become more affordable for us enthusiasts then we'll play too!
WOW MediaMan... Great article. Clear and very well written.
Good article, but one thing: In AMD's Dual Core implementation the cores are NOT linked together using HyperTransport. They uses a more direct coupling called SRQ (System Request Queue). The advantage is that cache coherencey updates between the cores are much faster. I.e. AMD's dual core implementation is no different to it's single core cousin with respect to HyperTransport/crossbar/memory-controller. Of course Hypertransport-Links can be used to extend the system with further CPUs, but that is a differnent story.
Good article! The best is that it explains things in a way that you don't need to be an engineer or a mathematic professor to understand most of it
I usually understand most of more advanced articles, but why make it more complicated then necesary?
I wouldn't be to suprised if AMD releases dualcore versions of their Opteron 1XX, Opteron 2XX and Opteron 8XX CPU,s in 2005 and not just for the heck of it. A system with 8 dualcore Opteron 8XX CPU's would ofcourse be 16 cores in total.
But I don't think Socket940 will be big in the enthusiast market. Sure some will ofcourse get it, just like there are allready some enthusiasts that have Dual Pentium III/Athlon MP/Xeon/Opteron systems. But I think most enthusiast will get dual core Socket939 Athlons, that probobly will be released in late 2005.
Some may want/need ECC memory and get Socket940 instead or need more then one dualcore processor for the specialized personal use, but I think the Socket939 platform will be more popular.
The one who lives will see.
Funny thing about enthusiasts...we all look for the best deal and sometimes whine about the high cost...but tally up what we actually spend on the entire box. It'll be much more than the average user. We're funny that way.
You are on target that Socket 940 will not be as popular with the enthusiast. Socket 940 wasn't designed for the enthusiast really. Socket 939 is better suited first and foremost because of its ability to use "normal" memory rather than the more expensive REG ECC.
Think of Socket 940 more for the performance workstation. It's a lot of horsepower with the benefits that pertain to ECC REG memory.
By coming out with a BIG impressive Socket 940 FX processor...it grabs the headlines. It says "Hey...look at AMD!". Then AMD can follow up with other products once they have the attention of the readers.
It's the same philosophy as having a loss leader item on sale at a store. The loss leader item brings shoppers in. Very few of them may purchase it but they are in the store...they'll most likely pick up other things while they are there.
Yes, it's not getting from A to B that mathers, it's how much fun you had getting there that counts :P
That statement works somewhat better when you look at cars and motorcycles then computers, but computers can be fun to
Yes, AMD allready do Socket939 version of Athlon 64 FX though. But a Opteron 2XX system will still be nice. If you get that when dualcore gets out that means 4 cores instead, not to shabby
MediaMan, great work man.
I've just finished my English homework, we were supposed to find an interesting article and write a summary of it, and of course, I chose this yours.
Keep up the good work.
/SpinBoy
I think you should title your page, AMD Hype.
Or not, because AMD announced dual-core CPUs first, and that's what the article is based on.
Acid-
I believe that this is one of the best non-biased articles I have ever read pertaining to processor technology. Bravo.
MediaMan, I think you missed your calling. You should have been a school teacher. With a article that well written even the class clowns would get an "A" on their exam....bloody good m8..
IBM have had a dual core server chip out for years, so saying that AMD engineers have "cracked" anything is perhaps innaccurate, all they have done is brought the option of a dual core cpu down to the pc level.
And thats what matters to us now isnt it.
I don't understand how an app (e.g. Photoshop) could take advantage of an SMP. I mean, doesn't the OS "shield" the hardware from the apps? Applicantions are not supposed to know about whether it is a uniprocessor, an SMP, or a dual-core, right? And what if the app knows it's SMP or dual-core, but the OS doesn't support SMP or dual core? Is it possible? Thx.
sorry that i have to make a comment about 64 bit processors here, because there is no 'comment' feature in the "64-bit simplified" article.
What on earth is a 64-bit processor? Does it mean 64-bit data bus? 64-bit control bus? 64-bit registers? 64-bit everything?
The OS doesn't do any more shielding from apps these days than buffer overflow protection with the NX/EDB bits on Intel/AMD processors. Applications, the OS, and the hardware is designed to let the application know if SMP exists explicitly for the purpose of taking advantage of it. Applications are most certainly supposed to know. Additionally, if the OS doesn't support SMP, the application has no idea -- it's all fed directly from the OS.
In computers, a 64-bit processor is one in which data is processed and/or stored in 64-bit chunks. The term often refers to the size of the CPU's registers that holds memory adddresses and other data, as well as the arithmetic logic unit that operates on those registers to compute. Busses have been varying widths for ages, with the Athlon XP being a 32 bit CPU with a 64 bit bus (Twin 32 bit pipelines) -- the Athlon 64 has a 64 bit memory-to-CPU bus, and a hypertransport bus which is CPU-to-chipset and it's 16bit bi-directional. A computer architecture described as "64-bit" generally has integer registers that are 64 bits wide and thus directly supports dealing both internally and externally with 64-bit "chunks" of data.
Bus widths don't count in the equation.
if more info needed i will register
Nice article, very informative.
gimme gimme gimme !!!
Great article, Thanks!
I do have a question ! Will these processers be more ESD sensitive that
the commonly used ?? Will special precautions have to be taken ?
JG
For those who may not understand the previous poster's question;
ESD = Electro Static Discharge.
ESD is a term most commonly used when handling/transporting electronic equipment such as microprocessors. I would imagine that the dual core processor would be handled with the same precautions as a single core processor. The ESD risk would be the same.
Excellent! Excellent! Excellent!
Thanks
Wow this came out of the wood works...
Thank you so much for putting together such a great article. This is the best explanation I ever got about the dual-core technology so far, and, finally, I start to understand how things work.
thanks man
i learnt a lot!
thanx
Awesome breakdown!
Quick question:
I saw some computers advertised on ebay with intel core duo procs. The seller claimed the the Ghz rating applied to each core, making a dual-core 2.0Ghz chip actually clock at a total speed of 4Ghz all together.
Is this anywhere near true? Seems oversimplified to me.
It's not true. The cpu still clocks at 2ghz. The seller is using pseudoscientific fakery to make the thing sound better than it is. That is not to say that a dual core 2.0ghz is a slouch. It is a cutting edge machine. The seller should be more honest - that thing could sell itself without relying on that kind of bullcrap.