by Ilya Gavrichenkov
02/08/2008 | 07:42 PM
The list of new solutions that Intel has streamed down onto the processor market hasn’t been exhausted yet. Mastering of 45nm production technology allowed the company to refresh their entire product lineup, and Intel continues working on it still. Top processors acquire new faster and more economical cores, while mainstream CPUs and their low-cost counterparts keep conquering higher clock speeds day by day. We have already devoted a few articles on our site to the currently happening lineup refresh, however, there are still a few hot topics left top be discussed.
The thing is that 45nm technology has only settled in the dual-core Wolfdale processors so far. The quad-core CPUs are not rushing to move over to the new production technology. Although three processors on new cores from the Core 2 Quad family were mentioned among the solutions announced in early January 2008, they haven’t started shipping yet. In fact, there is only one quad-core Yorkfield processor currently available in stores: the unacceptably expensive Core 2 Extreme QX9650, which can hardly be regarded as a popular and widespread solution.
As for the shipments of more mainstream Yorkfield processor models, there is a small delay here, because the engineers needed more time to fix the problems with processor stability in systems built around some types of mainboards. However, this delay will very unlikely affect Intel’s situation in the market. Today’s quad-core AMD processors from Phenom family cannot compete even with the slowest Core 2 Quad CPUs of the previous-generation. Therefore, Intel got a great opportunity to get rid of the older processor stock.
Nevertheless, Intel cannot hold off the launch of mainstream quad-core Yorkfield processors any longer. The market has already been warmed up enough with dual-core Wolfdale CPUs that demonstrated their convincing advantage in consumer features over the predecessors. As for quad-core CPUs Intel traditionally designs them as a combination of two dual-core dies in a single packaging that is why the users are very impatient to see the new Yorkfield processors that would represent a combination of two Wolfdales in a single packaging. New Core 2 Quad processors based on 45nm cores should boast all those advantages that made the new Core 2 Duo E8000 series extremely popular from day one.
At the same time, the new Yorkfiled processors selling under Core 2 Quad Q9000 series brand name will hardly enjoy as much demand as their E8000 counterparts. These CPUs will be relatively expensive, their official prices will start at $266 – the top price point for dual-core Core 2 Duo. However, although quad-core processors haven’t been any cheaper before, they are becoming popular very rapidly, mostly thanks to the youngest model in the lineup – the Core 2 Quad Q6600. When Yorkfield will actually come out, 45nm quad-core Core 2 Quad Q9300 will also be offered at about the same price and with the time it will replace its predecessor completely. Of course, this model from the refreshed Core 2 Quad family will become the most interesting solution.
That is why while everyone is still waiting impatiently for the promising Core 2 Quad Q9300 to appear in stores in early March, we would like to give you the opportunity to check it out in our detailed review.
We have already discussed new quad-core Penryn processors in detail in our Core 2 Extreme QX9650 Review. All in all, our today’s hero, Core 2 Quad Q9300, doesn’t differ from the QX9650 from architectural standpoint. It is built with two dual-core semiconductor Wolfdale dies stuffed into a single processor packaging. These dies communicate with one another via the front side bus and system memory, just like the dies of the quad-core Kentsfield processors.
The clock frequency of Core 2 Quad Q9300 processor, the youngest Yorkfield CPU, is 2.5GHz, the front side bus frequency is 333MHz (1333MHz quad-pumped). Just like Wolfdale processors, Yorkfield supports fractional multipliers with 0.5x increment, which explains where its unusual clock frequency comes from: it is obtained with a 7.5x multiplier.
Compared with other members of Core 2 Quad Q9000 processor family, the solution reviewed today boasts one distinguishing feature: smaller L2 cache. Instead of the 6MB for each pair of cores we would expect it to have, Core 2 Quad Q9300 has the total of 6MB of L2 cache memory. In other words, each of the dual-core dies within this processor features an L2 cache half the size: only 3MB.
Diagnostic utilities, such as CPU-Z, for instance, detect this peculiarity flawlessly:
The screenshots above reveal all the major characteristics of our today’s processor. Note that the CPU we tested has C0 core stepping that is also used in dual-core Core 2 Duo E8000. Nevertheless, this core stepping will not be used in mass production, it will be replaced with C1 (or M1) core stepping, which will be free from bugs that delayed mass shipments of Core 2 Quad Q9000 CPUs. However, you shouldn’t expect the new core stepping to bring in any significant improvements. According to Intel, there will be nothing new in its electrical, thermal or mechanical characteristics.
Here I would only like to say that the official price of Core 2 Quad Q9300 is set at $266. This way, the new Core 2 Quad Q9300 with 45nm cores will come to replace Core 2 Quad Q6600, so it makes perfect sense to compare them side by side:
Besides micro-architectural improvements such as new SSE4.1 instructions support and introduction of faster Fast Radix-16 Divider and Super Shuffle Engine functional units, Core 2 Quad Q9300 is superior to its predecessor in clock frequency and bus speed. However, its L2 cache memory is smaller than that of Core 2 Quad Q6600.
How critical is that for the performance? Let’s find out!
We ended up having a few platforms with different processors participating in our test session. We considered the main objective of this test session to compare the performance of all contemporary processors that could be purchased for the same price as that of Core 2 Quad Q9300. It means that the list of our testing participants included not only the quad-core Kentsfield processor – Core 2 Quad Q6600, but also top dual-core Core 2 Duo E8500 and Core 2 Duo E6850, priced officially at the same $266. Of course, we also couldn’t leave out AMD Phenom 9600, which price is also very close.
As a result, the complete list of hardware components used to assemble our testbeds looked as follows:
The first question that we tend to ask once we checked out the specifications of the new quad-core CPU is: will it be faster than the predecessor? We have already seen in case of dual-core CPUs, that Wolfdale processors easily outperform previous generation Core 2 Duo E6000 from the same price range. However, with dual-core processors is all very simple: Wolfdale CPUs have higher clock speeds and larger cache-memory than Conroe. As for quad-core Core 2 Quad Q9300, the situation is a little different. Although its clock speed is a little higher than that of Core 2 Quad Q6600, its L2 cache is smaller.
In order to dissipate all negative anticipations about Core 2 Quad Q9300 performance, we compared its results against those of Core 2 Quad Q6600:
The benchmark results indicate clearly that all our concerns were absolutely unfounded. Core 2 Quad Q9300 is faster than Core 2 Quad Q6600 even without a larger L2 cache, only thanks to architectural improvements introduced in Penryn processors, higher bus frequency and 100MHz higher clock speed. Moreover, there isn’t a single application where the old CPU would demonstrate higher results, and the overall performance advantage is about 7%, which is quite a lot.
Of course, the performance difference between the youngest Kentsfield and Yorkfield processors depends on the type of workload. Micro-architectural improvements bring in the highest performance improvement in final rendering and video content processing tasks. As for gaming applications, they are less optimistic towards Core 2 Quad Q9300, as they are sensitive to cache memory size.
So, the new quad-core Intel processor that will be selling for $266, is definitely at least as good as the old one. Moreover, it boasts one hidden advantage: it supports SSE4.1 instructions that will be more important a little later, when software applications using these instructions become numerous enough.
Core 2 Quad Q9300 has one more rival among Intel’s CPUs, besides Core 2 Quad Q6600. It is a dual-core Core 2 Duo E8500 that is also selling for $266 and is manufactured with 45nm process. Of course, there are users who work with specific applications and they know very well if they need more parallelism offered by a quad-core solution. However, many of you may have hard time trying to decide between Core 2 Quad Q9300 and Core 2 Duo E8500, when you see these two processors side by side in the official price list. Especially, since Core 2 Duo E8500 with a pair of cores runs at 27% higher clock speed, which may be much more important for some applications than an additional pair of cores onboard.
The table below should help you make the decision between the two. It shows the comparative performance data for Core 2 Quad Q9300 and Core 2 Duo E8500:
This picture is very ambiguous. There are still quite a lot of applications that haven’t been optimized for CPUs with more than two cores that is why Core 2 Quad Q9300 gets often defeated by Core 2 Duo E8500 due to the higher clock frequency of the latter. It is especially frustrating that games, even the latest ones, fall into the non-optimized applications category, as they still cannot use efficiently the advantages of multi-core micro-architecture. However, the situation is not as hopeless as it was 6 months ago, for instance. Game developers started paying some attention to optimizing their work for processors with more than two cores onboard. The list of games that provide quality quad-core processors support has increased significantly and currently includes such popular titles as Supreme Commander, Lost Planet: Extreme Condition, Unreal Tournament 3, Microsoft Flight Simulator X, etc.
As for those applications where quad-core Core 2 Quad Q9300 does demonstrate excellent results, I have to certainly mention rendering in 3D modeling systems. Video codecs are also quite optimized for multi-threading.
As a result, it is simply impossible to claim that Core 2 Quad Q9300 or Core 2 Duo E8500 win this race. Intel made a very wise move having priced these two processor models equally: the choice is now solely the user’s responsibility and to do it the right way he/she has to figure out what types of applications the system is being built for primarily. As for the general purpose systems (from the performance prospective), dual-core Core 2 Duo E8500 seems to be a little more optimal choice these days, while Core 2 Quad Q9300 will definitely be a better option for a long-term prospective, because more and more applications start to support multi-threading.
The youngest Yorkfield processor will probably also be a very interesting solution for overclocking fans, who hunt for maximum performance at the lowest price. It is not just the cheapest quad-core Intel processor, but also a progressive CPU from Penryn family manufacturing with the latest technological process.
At first glance Core 2 Quad Q9300 seems to be a very attractive candidate for overclocking experiments, at least since Core 2 Quad Q6600 used to be one like that. As you remember, we managed to easily overclock the youngest Kentsfield processor to 3.4-3.6GHz reaching unprecedented performance heights. We expect Core 2 Quad Q9300 to do even better than that: it is based on 45nm dies, each of which can run at 4.3-4.3GHz in Wolfdale processors. Moreover, we are also very optimistic because the top Yorkfield processor, Core 2 Extreme QX9650, overclocked to 4.0GHz in our previous experiments. All this contributes to very favorable informational background and creates highly positive overclocking aura around our today’s hero - Core 2 Quad Q9300.
However, Intel played a mean trick on enthusiasts when preparing their Core 2 Quad Q9300 and other CPUs from the same family for launch. This may totally ruin overclocking attractiveness of the new solutions. The thing is that Yorkfield processors, unlike their predecessors from the Kentsfield family, work with 333MHz FSB. And it automatically lowers the default clock frequency multipliers.
Thus, Core 2 Quad Q9300 with the nominal frequency of 2.5GHz featuring a 7.5x clock multiplier. It means that you will have to significantly increase the front side bus frequency in order to achieve any noticeable results during overclocking. For example, in order to clock Core 2 Quad Q9300 at 4GHz, which seems to be quite attainable for this processor theoretically, the FSB should be increased to unreal 533MHz. I said unreal, because none of the existing mainboards can work with quad-core processors at super-high FSB frequency like that. Numerous overclocking experiments show that the maximum FSB frequency contemporary mainboards can reach when working with quad-core processors and traditional cooling systems is 460-470MHz. That is why the typical overclocking result for Core 2 Quad Q9300 will be around 3.4-3.5GHz. Further frequency increase will be limited by the mainboard and the chipset, but not by the CPU that can definitely do better.
Now we have to check everything out in real life. For our experiments we used the same testbed as described above with ASUS P5E3 Deluxe mainboard on Intel X38 chipset. The processor was cooled with Scythe Infinity air cooler.
The obtained result falls precisely into our theoretical assumptions. Our system with Core 2 Quad Q9300 processor remained stable at maximum 467MHz FSB. As a result, we managed to overclock our CPU to 3.5GHz.
Overclocking quad-core processors by raising front side bus frequency is slightly different from the same overclocking approach for dual-core CPUs. It is in fact much more complicated. It is not enough to increase processor Vcore to ensure that it will run stably at high FSB speeds. To ensure stability you need to increase other voltages, too: CPU PLL Voltage, FSB Termination Voltage and NB Voltage. For example, when we overclocked our Core 2 Quad Q9300 to 3.5GHz we used the following settings:
I have to say that by skillfully manipulating secondary voltage settings, you can push the maximum FSB frequency a little bit higher. Therefore, it could be really good if the mainboard allows increasing CPU PLL Voltage, FSB Termination Voltage and NB Voltage significantly. There is one thing you have to keep in mind during overclocking like that through: increasing these voltages will inevitably lead to higher heat dissipation of the chipset North Bridge. That is why if you intend to use quad-core processors at over 460-470MHz FSB frequencies, you need not only to carefully pick your mainboard, but also modify the chipset North Bridge cooling system. By the way, this is when you could really use the mainboards where chipset heatsink can be connected to the liquid-cooling system, such as ASUS Maximus or ASUS Blitz, for instance.
Our overclocking stopped at 466MHz FSB not only because we didn’t feel confident to increase the chipset voltage any further, but also since the default chipset cooler on our platform wasn’t efficient enough. We also couldn’t push FSB Termination Voltage any further, because 1.5V was the maximum for the ASUS P5E3 Deluxe mainboard that we used for these tests.
Having obtained such unexpected overclocking result for Core 2 Quad Q9300, we were very interested to test this processor’s performance not only in nominal but also in overclocked mode. It will be competing against similarly priced Intel CPUs - Core 2 Quad Q6600, Core 2 Duo E8500 and Core 2 Duo E6850 - overclocked to their typical speeds.
Besides the above mentioned overclocked CPUs, we also included the results of the upcoming Core 2 Extreme QX9770 that should appear in the market together with other Yorkfield processors. As you know, this CPU works at nominal 3.2GHz frequency and supports 1600MHz bus.
SYSMark 2007 is an integral benchmark showing the systems performance in real applications of different types. That is why it is not surprising at all that the obtained results turned out very diverse: far not all the algorithms are optimized for quad-core processors. As you can see from the charts, Core 2 Quad Q9300 performs best of all during video processing. Here defeats all the competitors in nominal mode as well as during overclocking.
In other cases Core 2 Quad Q9300 yields to the new top dual-core Wolfdale processor, Core 2 Duo E8500, which boasts 26% higher nominal clock speed. Even overclocking doesn’t help, because it doesn’t really make up for the frequency difference between the quad- and the dual-core Penryn CPUs.
Note that overclocked to 3.5GHz Core 2 Quad Q9300 doesn’t lose to Core 2 Extreme QX9770 with twice as large L2 cache or to Core 2 Quad Q6600 overclocked to higher frequency of 3.6GHz. In other words, the youngest Yorkfield processor will not lose its attractiveness for computer enthusiasts even despite some overclocking mishaps.
We have already complained that quad-core processors support is not being adopted by gaming applications fast enough. The result is clearly seen on the diagrams: Core 2 Quad Q9300 is very often falling behind its dual-core competitor at default frequencies as well as during overclocking.
This situation is completely different from what we saw with previous generation processors on 65nm cores. Since Conroe and Kentsfield both overclocked to pretty similar frequencies, overclocked Core 2 Quad Q6600 ran neck and neck with overclocked Core 2 Duo E6850 even in games not optimized for quad-core. Now Core 2 Quad Q9300 cannot catch up with the overclocked Core 2 Duo E8500, so that overclocked have to face a really hard choice between a dual- and a quad-core processor.
Moreover, gaming benchmarks results reveal one more problem. During overclocking Core 2 Quad Q9300 sometimes falls not only behind its dual-core counterpart, but also behind its predecessor running at 3.6GHz frequency. This makes things even more confusing.
Video codec copes pretty well with multi-threaded workload that is why quad-core processors show their real best in corresponding benchmarks. Core 2 Quad Q9300 outperforms dual-core processors in all tests except audio encoding into MP3 format (that uses maximum two cores). However, the balance between Core 2 Quad Q9300 working at 3.5GHz and Core 2 Quad Q6600 overclocked to 3.6GHz is not always steady. For example, XviD 1.2 codec works faster in a system with an older CPU despite all the improvements and enhancements of the new Yorkfield processor. But when the new versions of these codecs start supporting SSE4.1 instructions, Core 2 Quad Q9300 should become a more confident winner.
When we compare the performance of dual-core and quad-core processors, the results of final rendering applications are the most illustrative ones. Today is also no exception.
We have to state once again that there is no unanimity in our today’s results. It is especially true for results of overclocked processors: Core 2 Quad Q9300 loses to the dual-core Core 2 Duo E8500 in Photoshop and Mathematica. In WinRAR and Mathematica it also falls behind Core 2 Quad Q6600.
We decided to conclude our review with the power consumption measurements for our systems (without the monitor) working in nominal as well as overclocked modes. The system configurations were the same as during our performance tests. Enhanced Intel SpeedStep and Cool’n’Quiet 2.0 power-saving technologies were activated. The processors were loaded with Prime95 25.5 utility.
Lower power consumption is one of the strengths of 45nm processors with four as well as two cores. No doubt that the new Core 2 Quad Q9300 turned out much more economical than its predecessor. Moreover, this quad-core CPU working at its nominal frequency can even be compared to the dual-core Core 2 Duo E8500 in terms of power consumption levels.
Overclocking, however, makes quad-core processors more “power-hungry” than the dual-core ones. That is why if you intend to overclock, you should keep in mind that the thermal and power parameters of your CPU as well as the entire system will increase dramatically. However, the new Core 2 Quad Q9300 can still be considered highly economical even when running at the frequencies far beyond the maximum, compared with the overclocked Core 2 Quad Q6600 from the Kentsfield generation.
The new quad-core Core 2 Quad Q9300 processor priced at $266 should be at least as demanded as its predecessor, Core 2 Quad Q6600. Being Intel’s cheapest quad-core processor built using the latest production process, this newcomer has a number of indisputable advantages: high clock speed, increase bus frequency, SSE4.1 instruction support and a few other micro-architectural improvements. Even despite the reduced to 6MB L2 cache, all these features ensure a pretty noticeable performance improvement. According to our tests, the average performance advantage of Core 2 Quad Q9300 over Core 2 Quad Q6600 is about 7%. And what is especially pleasing, you will get this performance gain absolutely for free: Core 2 Quad Q9300 will be priced officially exactly as Core 2 Quad Q6600.
In addition I would like to say that the use of more advanced manufacturing technology helped reduce power consumption and heat dissipation of the new processor. Our practical experiments revealed that it consumes about 30W less when running in heavy burn mode.
However, besides indisputable advantages, this new processor has one significant drawback, which may make the overclocker future of this solution quite doubtful. Although Yorkfield processors can overclock up to 4GHz (without any extreme cooling solutions involved), Core 2 Quad Q9300 cannot reach that frequency. Since the new quad-core generation started supporting 1333MHz bus, their multipliers got considerably lower. For example, Core 2 Quad Q9300 we have discussed today works with 7.5x multiplier, which doesn’t allow this processor to get past 3.4-3.5GHz because contemporary mainboards have pretty limited functionality when it comes to increasing the FSB frequency past 460-470MHz by quad-core CPUs. And this is actually even lower than the maximum frequency quad core processors from the Kentsfield family, including Core 2 Quad Q6600, can reach.
As a result, Core 2 Quad Q6600 may remain a better choice for overclocker systems, because it may run faster than Core 2 Quad Q9300 in some cases. Moreover, overclocking of previous-generation quad-core processors is a simpler procedure that doesn’t depend that much on the mainboard functionality.
So, it turns out pretty hard to make the final conclusion about the youngest quad-core Yorkfield processor. The new Core 2 Quad Q9300 is definitely a great product, but only until you get to overclocking. From the overclocking prospective we have to be more careful with our verdict and would call it an interesting but maybe not the most optimal choice.
Also, do not forget that quad-core processors can still hardly be considered an indisputably best choice. The applications optimized for multi-core micro-architecture are not that numerous yet. Therefore, dual-core processors with higher clock frequencies seem to be a more optimal solution. Our tests showed that new Core 2 Duo E8000 processors can outperform Core 2 Quad Q9300 in a number of tasks in both: nominal and overclocked modes.