When we postedbenchmark results of the new 3.06GHz Core i3 iMacand the new 21.5- and 27 - inch 3.2GHz Core i3 iMacs , most of those termination were in line with reasonable expectations . But there was one curious outlier : theHandBraketest grade .
The entry - stratum 3.06GHz Core i3 iMac do very similarly to the 3.2GHz Core i3 iMacs , with the 3.2GHz example averaging between 6 and 7 percent gamey scores in our overall system performance exam retinue , Speedmark 6 . Much of that difference , however , was due to pitiful performance on the HandBrake 0.9.3 encode test .
In our HandBrake test , we encode a chapter of a DVD movie to H.264 with two passes , secondly pass turbo enable , and scrap charge per unit set to 1500kbps . The 3.06GHz iMac select 3 minutes , 27 seconds to complete the test . The 3.2GHz fashion model finish in less than half the time , fill out the chore in just 1 minute 37 seconds . We tested and retested and used a different copy of the same DVD and found the same answer .
How we tested.We used HandBrake 0.9.3 and 0.9.4 to encode a DVD chapter to H.264 using 2-pass encoding, with turbo second pass enabled and Quality set to 1500kpbs average bit rate. We used Mac the Ripper to rip the DVD to the hard drive and then used the same settings to encode it using both versions of HandBrake. We imported a 55 minute and 11 second audio CD into iTunes as MP3 with Higher Settings selected. We then burned an audio CD of the songs using iTunes.
HandBrake 0.9.3 is not the latest version of the software program ; variant 0.9.4 was released just after we finalized our Speedmark 6 test suite . Many lector recommended retesting with the current version of the broadcast — made good sense to us , so we assay it . And while we found that 0.9.4 was imposingly faster than the late version , the problem remain . It still take twice as prospicient with the 3.06GHz iMac .
Though I initially assumed that these Modern iMacs would be using the same SuperDrive model , it turns out that they do n’t . The 3.06GHz Core i3 iMac come with an HL DT ST DVDRW GA32N opthalmic drive , which is from Hitachi - LG Data Storage . The 3.2GHz models come with a Pioneer DVRTS09 .
To do away with the optical drive from the equation , we ripped the movie to the concentrated cause first and then encoded the same chapter with the same setting from the file on the hard drive . In this test , we found both system of rules to do jolly much the same , with a departure of around two seconds , instead of 2X.
place the SuperDrive back into the equivalence , we tried another disk run , this clip importing a CD into iTunes as MP3s . This took precisely the same amount of clock time on both systems . Weird , huh ? It gets weirder . When we tried to combust the MP3s to an audio CD from iTunes , the Pioneer drive took longer than the HL drive . We did all of these tests multiple times , used the same media , same CD , etc .
I mouth to one of the HandBrake developer who thought maybe the HL drive usesriplock , where the drive slows down during DVD playback in parliamentary law to tighten noise from the drive mechanics . If the ride think that it ’s playing back a movie ( and does n’t clear I ’m judge to make a legal reliever of the copy - protect picture show while holding a stopwatch ) then perhaps it ’s throttling down a bit for a more still operation , and thus , affecting the execution .
Of course , you ca n’t make your buying determination based on what optical drive you prefer . Apple does n’t delimitate what sword of optical drive they ’ll let in , just as it does n’t condition the brand of gruelling crusade it uses .
New iMacs SuperDrive performance
Scale = Minutes : Seconds
How we tested . We used HandBrake 0.9.3 and 0.9.4 to encode a DVD chapter to H.264 using 2 - mountain pass encoding , with turbo 2nd straits enabled and Quality set to 1500kpbs average bit rate . We used Mac the Ripper to rip the videodisc to the tough driveway and then used the same scene to encode it using both versions of HandBrake . We imported a 55 instant and 11 2nd audio CD into iTunes as MP3 with Higher configurations select . We then burn an audio CD of the song using iTunes .
[ James Galbraith is Macworld ’s lab director . ]
