Any time Apple release updated ironware , there ’s a clamoring for definitive numbers on how the new system perform . It ’s no different with the update MacBook Pro model Apple announced Tuesday ; Macworld research laboratory director James Galbraith is already cut across down new laptops to prove , and we ’ll publish the results at Macworld.com just as soon as we have the numbers .

But this time around , we already have some idea of how the Core 2 twosome - powered MacBook Pro will perform comparative to its forerunner before a single bench mark is even total . That ’s because Apple already made such a transposition last month , when it updated the iMac Core Duo cable by add next - generation Core 2 Duo chip .

In our initial benchmark testing for the update iMacs , we equate a 17 - in iMac running on a 2GHz Core 2 twosome mainframe with a 20 - inch 2GHz mannequin powered by an sr. Core Duo chip . The Core 2 couple car posted a 10 pct betterment over the old iMac in our Speedmark 4.5 test . In all but one of the single tests , the iMac Core 2 couplet ran quicker than the iMac Core Duo with the same central processing unit speed , with gains between 10 and 20 percentage depending on the test . The one test where the Core 2 duet machine was n’t faster ? Creating a Zip archive in the Finder from a 1 GB folder ; the two iMacs posted the same grudge in that tryout .

Here ’s what James Galbraith wrote about those iMac result :

Now those run results plausibly wo n’t synchronise up exactly with what our Lab rule when it compare the 2.16GHz MacBook Pro Core 2 Duo with its Core Duo counterpart . After all , a laptop is n’t a desktop — though the iMac expend a muckle of laptop components , and the MacBook Pro , like the iMac , has doubled its shared L2 cache to 4 megabit . And there are other changes to the MacBook Pro that we either know about ( like the bigger hard drives ) or that we ’ll find out out about soon enough that could further bolster operation .

( Also deserving mentioning : our colleague atPC Worldran some tests back in September on Core 2 yoke crisp in microcomputer laptops . They found only a small public presentation hike in portable featuring the fresh chip . Again , a PC is not a Mac , as anyone who has used the latter will be well-chosen to tell you , so these effect may not fit with what we find once we have a newfangled MacBook Pro in hand . )

When Intel introduced its Core 2 Duo chip this summer , CEO Paul Otellini promised a 20 percent increase in laptop computer performance over the Core Duo while maintain the same assault and battery life . Apple is making more radical claims — gains of up to 39 pct over the previous version of the MacBook Pro . It will be interesting once we get these new models into the Lab to see who ’s right .