Macworld has a performance test of the new dual core iMac vs. the old G5 iMac. They are saying, that the new Dual Core iMacs don’t perform twice as fast, and seem quite a bit disappointed.
I think, they just aren’t comparing Apples to Apples. Let me explain:
The old iMac is a single processor G5. The new iMac a Dual Core Intel chip. The applications they are testing (iMovie, iPhoto, iTunes, creating a ZIP file, iDVD and BBEdit) are most likely (correct me if I’m wrong, please) single threaded applications. That means, that the raw work of converting, compressing, searching and whatnot is running on a single core. Only applications that are built to be multi-threaded would be able to share the work on both cores. So what the test results are showing us (imo) is that the Intel Dual Core processor running an application on basically one of it’s core is a wee bit faster than the G5.
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