The Real World Rules!
While it’s great to use software like PCMark and SYSMark to get an idea of how a PC performs in various scenarios (and they are getting even better, benchmarking within real-world applications), nothing beats doing the tests yourself to see exactly where each CPU model excels and falls behind in performance.
The one thing our readers are most interested in, after gaming, is probably video and audio transcoding. After all, who wants to keep music on annoying discs? The same can often be said for video, as today’s huge hard drives allow us to store a lot of movies.
Audio Encoding
For our audio encoding tests, we use the latest version of dBpoweramp Music Converter (at this time, R13). This program has the slickest interface I’ve seen for an audio converter, as it integrates into the Windows Explorer shell (right click > convert to). It also supports a plethora of codecs, although we’re only going to look at the three main ones – MP3, Apple Lossless, and WMA.
Both MP3 and WMA were run in Constant Bit Rate, converting an entire CD to 128 kbps. WMA was also run in Lossless mode, along with Apple Lossless.
We have recently updated this test to support multi-threading capabilities offered by dBpoweramp. We used to benchmark the conversion of a single large track, but that only ever used one thread. With the latest version of the software, you can encode up to four tracks at once. So from now on, we will be encoding a group of 26 tracks, ripped directly from a CD in WAV format.
Depending on the codec being used, music encoding can scale really well, or not very well at all. In most cases, Core i7 is right in line with the Penryn results, but obviously excels quite a bit with Apple Lossless, which is probably the most threaded of the bunch.
Video Encoding
As usual, we are converting a portion of Groundhog Day DVD to MPEG-4 Part 2 using VirtualDub. The codecs we’re using are DivX, which is multi-threaded and getting better with every version, and the still single-threaded XviD, which “the scene” still prefers to use for some reason.
I am going to look into something a little more up to date for our next review, using HDTV source material and a more modern MPEG-4 AVC codec. Since DivX and XviD are so widely used, I’ll probably keep this as an SD video transcoding scenario. If someone knows of a good HD encoding method that is easy to run and keeps track of encoding time, please let me know.
I actually expected the Divx results to scale much better than they do here, or at least more than the single-threaded XviD test. We saw incredible gains when Hyper-Threading was introduced to the Pentium 4 Northwood, but unfortunately no such thing is occuring here. I guess 4 cores is enough for now.
iPod Video Encoding
Here’s a new test, based on another real-world scenario. Say you want to have some music videos on your iPod or iPhone. What do you do? If you’re a clueless Apple fanboy drone, you probably shell out $1.50 on iTunes for each one. But if you know better, you could just grab the videos from Youtube, quickly convert them with whatever software you wish, and transfer them to your device with Winamp or whatever (Youtube is even starting to offer direct MP4 downloads which should be compatible as well, so this test is going to be outdated pretty soon anyway).
In this test, we are using ImToo converter to encode 10 music videos from Youtube’s FLV format to iPod-friendly MP4 format. This program is multi-threaded, converting as many videos as possible (the limit can be increased to whatever you want).
This is one of the tests where we see standard scaling, then the i7 965 pulls way ahead of the pack. The only thing different is the QPI speed, so it must be benefiting from increased bandwidth here.
[...] we mentioned in our initial review of the Intel Core i7 Nehalem platform, the 920 and 940 run with different speeds than the 965 – beyond just the clock speed. The actual [...]
[...] looms in the same price range; the CPU itself is just $10 more than a Q9550. As you recall, when we first reviewed the Core i7 series, the X58-based motherboard required to run these CPUs were ridiculously priced ($285 was about the [...]
[...] links, 4 memory channels, and support for up to 16 memory modules per channel. As we said in our Core i7 review, the Nehalem core is extraordinarily versatile due to its modular nature. We’ll see this in [...]
[...] They take everything that makes the original Core i7 so great – and you should read our original Nehalem review if you want a refresher on what that entails – and makes it more suitable for the desktop [...]
[...] the same, including Turbo Boost, HyperThreading, etc. You can read about all that in our original Nehalem review. One addition that was made is AES-NI encryption/decryption acceleration, which adds 12 new [...]