Since its release in January , Apple ’s MacBook Pro has been a blistering item . Now that an updated version with a fresh CPU is merchant marine , Mac users are hoping that the laptop is a little less hot in one country in finical — their laps .

The newMacBook Pro Core 2 Duo modelsgenerally run cooler than their predecessors — though not enough for users to notice . Testing by Macworld Lab find that the transposition from the Core Duo C.P.U. to Intel ’s next - propagation Core 2 Duo offering slightly dilute the 2.16GHz MacBook Pro ’s persistent feverishness . However , the 2.33GHz theoretical account got just as hot as its Core Duo counterpart . Still , regard the Core 2 Duo ’s higher-ranking speed and power , these event show improvement in the MacBook Pro ’s organisation - cooling engineering science .

What we found

Using the surface probe of an infrared thermometer , we measured outside temperatures in the same “ hot spots ” for each notebook — the legal profession above the F - keys and the area surrounding the barrage . The 15 - inch 2.33GHz MacBook Pro Core 2 Duo attain 117.9 degree ( Fahrenheit ) above the keyboard and 116.6 degrees in the country near the electric battery . That compares to mellow temperature of 116.9 and 116.1 degrees , respectively , for the 15 - inch 2.16GHz MacBook Pro Core Duo . But compare organization with the same clock speed , the 2.16GHz MacBook Pro Core 2 couplet peaked at 110.3 and 109.8 degrees — a slight decrease from the old Core Duo systems . ( By manner of comparison , a 2GHz MacBook with a Core Duo central processing unit showed tip temperatures of 105.1 and 101.8 degrees , while a 15 - inch 1.67GHz PowerBook G4 heat up to 112.5 and 112.3 degree . )

Core 2 Duo Temperature Tests

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All solvent are in Fahrenheit . To measure extraneous temperatures , we used an infrared thermometer to get readings on the bar above the F - keys and the region skirt the assault and battery on each laptop . Temperatures were measured while converting MP3 files in iTunes . Internal temperature were immortalise using the CoreDuoTemp app ; because the programme does not melt down on PowerPC - based Macs , we could not use CoreDuo Temp to record the internal temperature of the PowerBook G4.—MACWORLD LAB TESTING BY BRIAN CHEN

Of course , it ’s not just what ’s outside that counts . We ranCoreDuoTemp , an software that measures internal temperature of Intel - based Macs . The free program enter in high spirits internal temperatures of 178 and 174 degrees for the 2.33GHz and 2.16GHz Core 2 duad models , severally . The 2.16GHz MacBook Pro Core Duo touch 176 degree , while the 2GHz shameful MacBook peaked at 167 . ( We leave out the PowerBook G4 from this mental test since it ’s uncongenial with CoreDuoTemp . ) All testing take place in a kiosk with a elbow room temperature of roughly 74 degrees ; each simple machine hold 1 GB of RAM and fly the coop MP3 conversions on iTunes for 40 minutes .

That the 2.16GHz MacBook Pro Core 2 Duo produced cooler effect than a Core Duo laptop with the same clock pep pill indicate that Intel is making strides with producing more powerful chip that use less energy . In fact , since this most recent round of MacBook Pro updates featured no major changes to the interior of the machine ( save for the chip swap ) , it would be fair to say that Intel is taking the lead role in keeping the MacBook Pro ’s temperature steady . ( An Apple representative order us that both the previous and later crease of MacBook Pros are “ observably cool ” because of firmware update released in May and June that adjusted fan speeds . It ’s reasonable to assume that succeeding microcode update could produce similar result for the latest MacBook Pro example . )

There still is n’t a try - and - truthful method acting of temperature testing , so we welcome input from MacBook Pro users on these results . What are you doing with your MacBook Pros when they start to heat up ? After some experimentation ( with Quake 4 , Adobe Photoshop CS2 Automator actions and DVD playback ) , iTunes ’ MP3 conversion heated up the MacBook Pros for us the most .

Since these test were all run on machines with screens no bombastic than 15 inches , we ’re thirstily awaiting the arrival of the 17 - inch 2.33GHz MacBook Pro Core 2 duet . Stay tuned for upper and temperature results for that laptop as well .

[ Brian Chen is an assistant editor forMacworld . ]