by Anna Filatova
09/28/2006 | 12:00 PM
I believe that no one doubts that further development of computer platforms will take the way of increased parallelism. The dual-core processors that used to be something outstanding a while ago have taken a very steady position in the market these days. And by the end of this year hardware enthusiasts have every chance to become happy owners of quad-core systems already.
At the Intel Developer Forum Fall 2006 that is finishing today in San Francisco, Intel paid special attention to the quad-core desktop processors that will be coming out in Q4 this year known as Kentsfield. Therefore, we decided to devote the whole separate article to this product, where we will proudly share all the details with you.
However, you shouldn’t think that AMD will have nothing to respond to Intel’s quad-core design. Inside AMD labs the engineers are working hard on the 4x4 project that should also be announced before the end of the year. However, unlike Intel, AMD is going to offer the gaming enthusiasts not a single quad-core CPU, but a dual-processor system built on dual-core processors. Time will show which approach becomes more successful, and in the meanwhile let’s return to our today’s hero – Intel Kentsfield CPU.
Intel’s plans are truly tremendous. With the first quad-core processors they intend to deliver the 10x performance improvement by 2008 compared with the regular Intel Pentium 4. Over the last couple of years they made changes to focus on the multi-core.
Now the expected performance processor is a dual-core one. In early November Kentsfield will come out and it will be a quad-core solution. Each one of these cores will be the most power-efficient thing that can be developed. Here I would like to point out that the upcoming launch of the quad-core Kentsfield processor that will be one more great offering for the desktop platforms, does not mean that dual-core Core 2 Extreme CPUs got to be discontinued. At first Intel will only be offering Kentsfield as a premium solution in the same market segment as Conroe. And it will remain this way until the existing software infrastructure learns to take real advantage of all multi-core processor design benefits.
What is quad-core processing? It means that the CPU has four physical processing cores in one package and the package fits into the existing infrastructure that we have. In other words, it means that the upcoming launch of the quad-core solutions will not require any massive platform changes. In fact, the same platforms will be able to work with both: dual-core Conroe CPUs as well as quad-core Kentsfield.
Intel engineers decided not to design any principally new processor solution that would combine four cores on a single semiconductor die. Kentsfield will consist of two physical dies each of which is a monolithic core. From this prospective, Kentsfield is very similar to the dual-core Smithfield processors on NetBurst micro-architecture, where there simply were two cores mounted onto a single processor board. Intel is going to do the same thing this time. In fact, Kentsfield is none other but two Conroe processors joint together in a single processor casing at the packaging stage.
There are a lot of advantages to this approach. However the primary one is simple production process. With this multi-chip approach Intel gets at least 10% cost savings during manufacturing. They practically share the same dies and manufacturing facilities for building dual-core and quad-core processors. They can select the best die on the wafer to achieve the power and performance characteristics for the quad-core processor. So, it helps with the supply.
The product is based on the Core micro-architecture, the same design that is used in Core 2 Duo. It is an energy efficient design. No part of the circuitry is powered on unless we need it. Intel will be able to offer quad-core in volume offering 80W thermal envelope. With that configuration they promise us 50% increase in performance. And finally they will also have lower power offering with 50W power consumption for the dense computer environments.
Let’s say a few words about the upcoming company roadmap. We can expect the first quad-core product in the extreme segment in November. It will be extension of Core 2 Extreme. Intel already has the world's highest performance processor in the desktop segment, and they will increase the performance lead by offering Kentsfield, which will go into the same platform as the today's Core 2 Extreme. In 2007 Intel will be offering their mainstream desktop solution – an extension of Core 2 processors also known as Core 2 Quad at a number of price points that will ramp across the year 2007. Penryn and Nahalem families will be the next-generation designs (manufactured with 45nm production process).
The situation in the server space is a little bit more complicated.
The first Kentsfield processors that will be released in early November will be targeted for computer enthusiasts. It will be launched under the name of Core 2 Extreme QX6700. Its clock speed will be slightly lower than that of the top Conroe processor and will equal 2.66GHz. Kentsfield will support the same processor bus with 1066MHz frequency. The total L2 cache size will be 8MB – 4MB for each dual-core half of the CPU. The processor will support the complete set of power-saving technologies of the Conroe CPU.
Kentsfield will require the mainboard features the proper BIOS support, but fundamentally all mainboards should support it. All the power management features will also work as they should. Although later on in this article when we get down to discussing some benchmark results you will notice that we used D975XBX2 Rev.303 mainboard, you should keep in mind that it is a pre-production sample, and when it comes to shipments, you will see a newer second-generation Bad Axe 2 Rev.400 board. And the pricing policy will be the same as with entire Extreme series.
I have to say that Kentsfield is a very innovative product that goes far ahead of the software applications that can take advantage of its potential. According to forecasts, highly-threaded games should start ramping in 2007, at least 6 months after Kentsfield for enthusiasts is already out.
Intel already has Kentsfield samples ready and their closest partners are already testing them in their labs. However they haven’t yet given any reviewers a chance to take a closer look at the new processor, partially because the first quad-core processor revisions suffered from extremely high power consumption and heat dissipation.
However today these issues have been resolved and at the IDF Fall 2006 we could see a lot of working systems with the promising quad-core Core 2 Extreme QX6700 (Kentsfield). Luckily, Intel gave us a great opportunity not only to watch these systems at work but also to play with them on our own. I certainly couldn’t miss this opportunity and ran the first preliminary benchmarks on the first Core 2 Extreme QX6700 based system. The results were compared with those of the today’s top dual-core processor – Core 2 Extreme X6800.
The testbed was configured as follows:
I would like to stress once again that the tests were performed outside of our usual lab at the Intel IDF booth, therefore Intel engineers took the trouble to set the system. This is once of the main reasons why we insist on regarding the obtained results as preliminary.
This is what the system on Core 2 Extreme QX6700 looked like inside:
As I have already mentioned before it featured a new Intel D975XBX2 (BadAxe 2) mainboard.
The quad-core Core 2 Extreme QX6700 processor is recognized by Windows XP Professional SP2 correctly and it sees it as four separate processors:
By the way, this is not a new picture for us. As you remember, we could see similar picture in systems with dual-core Pentium Extreme Edition on NetBurst micro-architecture. These processors had two physical cores and two virtual cores thanks to Hyper-Threading technology.
The CPU-Z utility version 1.36 is also familiar with Kentsfield:
Everything is detected correctly except for the CPU name. It even detects the correct cache size that consists of two 4MB L2 caches of the Conroe processors used to build the Kentsfield.
We didn’t have the chance to run a lot of benchmarks, because of the limited time with the systems we had at our disposal, however we would still like to share some of the obtained results.
PCMark05 test is relatively old therefore it hardly uses the potential of the four computational cores in this system. That is why Core 2 Extreme X6800 working at higher clock speed wins in the total score chart. 3DMark06 is more intellectual from this prospective, and it creates fully-fledged multi-threaded workload in processor subtests. The result is evident of course: the winner is the quad-core Kentsfield CPU despite its lower clock speed compared with that of the tested Conroe model.
However these are synthetic tests that have very little to do with real-life applications. Especially, since there are no games that can take real advantage of all four processor cores. Therefore, Intel didn’t let the reviewers to run any games during the hands-on test session.
But there are certainly other applications that can give you the feel of the actual quad-core power. For example, the DiVX 6.2.5 codec that shows considerably better results during High Definition content encoding by splitting the work into 4 parallel processes.
As we see, Kenstfield processor working at 2.66GHz outperforms Core 2 Extreme X6800 working at higher frequency of 2.93GHz by over 35%.
We see very similar situation during non-linear video editing performed with Sony Vegas tool.
The new processor is over 50% ahead of the predecessor here!
Of course, we couldn’t leave out final rendering tests in 3D modeling applications, because it can be split into parallel processes very efficiently.
During the rendering of the scene on the picture below performed in POV-Ray we obtained the following results:
The quad-core CPU is beyond any possible reach here: it is 80% faster than the predecessor!
In 3ds max 8 we rendered the following image:
The results are excellent again. Kentsfield is more than 60% ahead of the top dual-core solution.
So, Ketsfield may turn out extremely efficient in applications that can create parallel multi-threaded workload. Unfortunately, there are not that many tasks yet that could work this way. However, by launching this quad-core monster into the world Intel definitely creates very favorable grounds for the new stage in software development – parallel data processing. And the game developers will be the first ones to take real action in this direction, because at this time no game can rally load all the four cores of the Kentsfield processor.
Nevertheless, if you are into 3D modeling or video editing, then it would definitely make sense to upgrade to a quad-core platform as soon as you can. Conroe processors have set a new performance bar for the high-end systems and Kentsfield raises this bar even higher. The performance level you couldn’t even dream of a year ago can now be easily conquered by the new quad-core Kentsfield processor.
I would like to specifically stress that the introduction of quad-core Kentsfield processors will also improve the performance-per-watt ratio significantly. According to Intel, these CPUs shouldn’t consume much more power than the top Conroe processors. At the same time, the performance growth may reach up to 80% (if the applications are well optimized, of course), which we have just see in our preliminary test session.
Well, I would like to wind up our Kentsfield Performance Preview here. Very soon we will be able to offer you a detailed coverage where we will reveal more details, especially since some of the very acute questions haven’t been touched upon today at all. One of the most interesting questions would be the workload distribution across the computational cores with the shared or separate cache that may affect the performance in certain applications.