Performance during Audio and Video Encoding
First of all we will take a look at the audio encoding into mp3 format with a popular LAME codec. For our tests we used an unofficial codec version 3.97, which supports multi-threading and exists in 64-bit version.
During audio encoding, dual-core processors prove faster than their single-core fellows even though they work at lower clock frequencies. During audio encoding with a 32-bit codec, the laurels will be won by the dual-core Intel Pentium D 830. in case of a 64-bit version the situation will change. Strange as it might seem, but the 64-bit version of LAME is slower than the 32-bit one. Moreover, if the Athlon 64 processors get only 10% slower, then the Pentium 4 CPUs lose about 20% of their speed. As a result, the best performance in 64-bit LAM version belongs to Athlon 64 X2 3800+.
This relatively strange situation with the 64-bit version of LAME is most likely connected with the Microsoft compiler, which was used for the final code processing. However, in this “critical” situation, when the 64-bit program version appears slower than the 32-bit one, you can easily use the faster version in the 64-bit OS, even though it will require activating the compatibility mode.
There also exists a 64-bit version of the XviD codec. With this codec we tested the performance of our processors during video encoding in 64-bit and 32-bit operating system.
Well, no surprises here, not like in the previous case. The 64-bit codec version is evidently faster than the 32-bit one, although you will not be able to benefit from dual-core architecture in any way here. So, in the price group in question the best result was demonstrated by Athlon 64 3800+ processor.
Now let’s take a look at our testing participants in those codecs that do not have 64-bit revisions yet.
Despite its dual-core architecture and SSE3 instructions support, Athlon 64 X2 3800+ cannot win this race. Pentium D 830 appears the fastest here. Note that in this codec the dual-core AMD processor runs somewhat slower than its single-core fellow from the same price group, while the situation in Intel’s camp is just the contrary: single-core Pentium 4 650 gets defeated by the dual-core Pentium D 830.
The results obtained with the DivX codec are quite predictable. NetBurst architecture works better in this case than K8. Besides that, higher core clock frequency of the single-core processors appears more efficient here than the dual-core architecture, even though the application does support multi-threading. So, AMD Athlon 64 X2 and Pentium D processors cannot benefit from their second core that much here.
It is also very interesting that the 32-bit DivX codec works slightly faster than the 64-bit version of it in Microsoft Windows XP Professional x64 Edition OS. The advantage of the 32-bit program version makes about 3-5%.
During our previous dual-core processor testing sessions we have already mentioned a few times that Windows Media Encoder is an excellent example of an application using two processor cores. So, Athlon 64 X2 3800+ appears over 30% faster than Athlon 64 3800+, even though the dual-core processor works at 17% lower clock frequency. All in all, Athlon 64 X2 3800+ manages to defeat even Pentium D 830, although NetBurst architecture proves pretty efficient during media data encoding.