Audio and Video Transcoding
We use Apple iTunes utility to test audio transcoding speed. It transcodes the contents of a CD disk into AAC format. Note that the typical peculiarity of this utility is its ability to utilize only a pair of processor cores.
Strangely enough, the new Pentium processors suddenly yielded to their counterpart for the LGA775 platform. But if we disregard this one incident, then the overall performance of the new Pentium G850/G840/G620 processors will be quite acceptable. Previous-generation LGA1156 Core i3 and Pentium processors as well as dual- and triple-core Socket AM3 CPUs fall far behind our heroes.
In order to measure how fast our testing participants can transcode a video into H.264 format we used x264 HD benchmark. It works with an original MPEG-2 video recorded in 720p resolution with 4 Mbps bitrate. I have to say that the results of this test are of great practical value, because the x264 codec is also part of numerous popular transcoding utilities, such as HandBrake, MeGUI, VirtualDub, etc.
Video transcoding using x264 codec is one of those few tasks where the number of processor cores matters a lot. That is why the new Pentium CPUs can’t really shake the triple-core AMD processor as well as Core i3 CPUs. Although the latter processors are dual-core ones, they support Hyper-Threading technology. As for competition against true dual-core processors, our heroes are definitely in the lead.
The performance in Adobe Premiere Pro is determined by the time it takes to render a Blu-ray project with a HDV 1080p25 video into H.264 format and apply different special effects to it.
This looks very similar to what we have just seen in the previous benchmark. This is quite logical, because both - x264 and Adobe Media Encoder – create the same processor load.
We decided to add Cyberlink Media Espresso 6.5 to the list of benchmarks we use for video content trancoding. This utility is particularly interesting to us because it allows using the graphics accelerator for video transcoding. We measured the time it took to transcode a small 10-minute H.264 1080p video clip into an iPhone 4 friendly format (H.264, 1280x720, 4 Mbps). In all tests we enabled ATI Stream technology supported by our Radeon HD 6970 graphics card, which accelerated the transcoding process.
Compared with what we saw in other video transcoding applications, we do not notice anything new here. The new Pentium G850/G840/G620 yield only to triple-core CPUs or dual-core processors with Hyper-Threading support.
We use special Cinebench test to measure the final rendering speed in Maxon Cinema 4D.
Rendering, just like video transcoding, is one of those tasks that can use any number of available cores quite effectively. So the outcome of this test was quite expected. New Pentium processors for LGA1155 platform become the fastest dual-core CPUs, but at the same time they are defeated by the triple-core Athlon II X3 as well as the dual-core Core i3 CPUs with Hyper-Threading support, which doubles the number of computational threads executed simultaneously.
Rendering speed in Autodesk 3ds max 2011 with both, Scanline as well as Mental Ray, was measured using SPECapc test.
This is a different rendering application, but the results are practically the same. Pentium G850/G840/G620 processors can’t be regarded as a good choice for serious computational tasks. If you are looking to build an inexpensive system for rendering needs, it would make more sense to go for an inexpensive triple-core AMD CPU, which are currently selling at very democratic prices.