Test results
Our test procedure features two peculiarities of data representation: firstly, all data types are reduced to one - integer relative score (performance of a given processor relative to Intel Core 2 Quad Q6600, its performance taken for 100 points), and secondly, detailed results are published in a Microsoft Excel spreadsheet, while the article contains only summary charts for benchmark classes. Nevertheless, we'll sometimes draw your attention to detailed results, if they are worthy of your attention.
Professional tests
3D modelling and rendering
Quad-core processors seem to perform very well in this group (their advantage over dual-core processors is impressive). But if we have a look at the detailed results, you will see where it comes from in the average score. Owing to rendering speed tests, of course. It's not a secret that rendering can be easily distributed between many processors, and performance gains are close to ideal (100% per each new core). What concerns tests of interactive operations in 3D Modeling applications, the situation with quad-core processors is not that peachy anymore, and performance gains are limited to 10%.
CAD/CAM
It's an excellent example of absolute uselessness of quad-core processors for such software. Cannot be better: E6600 scores as many points as Q6600, E7200 is on a par with Q9300. The choice is crystal clear: "unassuming" dual-core processors, preferably on the new Wolfdale core.
Compiling
On one hand, we cannot say that there is no difference between dual-core and quad-core processors here. On the other hand, it's not that big. We monitored CPU load during compilation of this project (about 30 minutes) and noticed that it rarely used all four cores simultaneously, while periods with only one loaded core were quite lengthy. However, it's quite a typical project from the point of view of modern C++ style - so its compilation peculiarities are also typical.
Professional photo processing
It's the second test, where quad-core processors "broke loose". On the average, four cores are 30% as fast as two cores! You may object that the ideal advantage must reach 100%... But let's be realists: even 30% is a very good result these days, it's quite rare.
Scientific applications
Scientific software cannot boast of optimizations for quad-core processors: even if we have a look at detailed results, we'll see that the maximum performance gain from additional two cores is about 10%.
Web server
As we use two benchmarks, one of which (PHP Calculator) can use several threads, while the other (PHPSpeed) rarely uses even two cores - the average score is something in between. Indeed, quad-core processors enjoy almost 100% performance gains in PHP Calculator. And PHPSpeed needs mostly performance of a single core.
Total professional score
A difference between dual-core and quad-core processors in each of our competing pairs amounts to ten points. On one hand, it proves that our result is certainly not random or caused by a measurement error. On the other hand, 10-11% of performance gain as a result of twice as many cores is not impressive... But let's not forget that the total score is nothing but "the average temperature of patients in a hospital." If we analyze charts with detailed results, we can clearly see two groups on the common mediocre background - these are programs for 3D Modeling and professional photo processing (Adobe Photoshop). Quad-core processors demonstrate impressive results here. The other programs from our list of professional software still do not need four cores...
