We tested video encoding performance using VirtualDub-MPEG version 1.6.15 and a multithreaded version of the Xvid codec, along with the LAME MT MP3 encoder for encoding audio. We did a two-pass encode of a 15-minute 276MB digital TV recording with a target file size of 100MB.
With at most eight seconds difference (between E6700s) we still see the P23 out performing the P30 and this time around the E6750s outperform the E6700s as you'd expect.
MP3 Encoding:
We used LAME MT for our audio encoding test - it's the multithreaded version of the popular LAME MP3 encoder. We ran tests with both Intel's and Microsoft's compilers - naturally, the Intel compiler resulted in some performance increases on Intel's processors. We converted all 18 tracks from Moby's popular Play album to a 192kbps variable bit-rate MP3.
Using the Intel-optimised LAME 3.97 MP3 compiler, the P30 finally comes out faster in the E6750 comparison, however the E6700 is fractionally faster on the P23. In the Microsoft compiled version both P23 results are a fraction faster than the P30 yet again though.