Benchmark Results: Video Encoding
For video encoding testing, we've used a 1080p H.264 and AAC trailer for Nine Inch Nails' Beside You In Time, available on Apple's Quicktime HD gallery. Unlike many downloadable 1080p trailers, this 2:20 trailer has parts with very high-bitrates (30–45 Mbps), though the average bitrate is just 19.38 Mb/s.
1080p WMV with Windows Media Encoder 9
For WMV encoding, we’ve selected the High Definition Quality Video preset, but retain the source aspect ratio and size. Encoding bitrate is set by the profile at 5.3 Mbps. Everything else was set at default values. Although the encoding was done in two passes, we've decided to use the total time taken for encoding and not for each pass.
Video encoding tends to be very parallel, making use of all available cores.
If you do a lot of video encoding, you’ll get more things done quickly with a quad-core processor. A triple-core processor offers practically the same performance of a dual-core processor in this particular application. That’s because this title doesn't utilize the third core. Of course, if you’re using the computer for other tasks while encoding, that third core really comes in handy.
With only two cores utilized, the Phenom II X3 710 actually consumes more power than an Athlon II X2 250 in this benchmark. They are roughly the same at default settings and without power management. Because the encoding time is not much different, even the Athlon X2 7750 delivers interesting results. Though slightly slower, power consumption is about the same. Its consumption is still about 11 watts higher than the Athlon II X2 250 if you reduce the voltages, though.
With all cores running full speed, the Phenom II X4s come out again as the most efficient processors. Just look at total power consumption. Even without power management, the quad-core processors consumed less power while completing the task.
