6MB L2 vs. 3MB L2

Apple offers two CPU options for the MacBook and three for the MacBook Pro. The MacBook comes with a 2.1GHz Core 2 Duo with a 3MB L2 cache shared between both cores, or a 2.4GHz model also with a 3MB L2. The MacBook Pro comes with the same 2.4GHz/3MB part or a 2.5GHz Core 2 Duo with a 6MB L2 cache. The question is: how much benefit does the extra 3MB L2 cache give you?

Unfortunately Intel doesn't offer the same clock speed CPU in both 3MB and 6MB flavors, so we're left comparing two differently clocked CPUs. In this case we took a 2.4GHz/3MB Core 2 and stacked it up against a 2.5GHz/6MB part, the chart below shows the performance improvement of the 2.5GHz/6MB core over the 2.4GHz/3MB part:

The performance increase due to the clock speed and cache size increase varies from 0% all the way up to 11.7%, with a maximum of around 4% of that being due to the clock speed increase alone - the added L2 cache does have a benefit.

How much does Apple charge for the average 5% improvement in performance? Unfortunately you can't just purchase the CPU upgrade, you have to buy the $2499 model instead of the $1999 model. You get another 50GB of hard disk space (250GB vs. 200GB) and 512MB of video memory along with the CPU upgrade but you're paying an extra $500. Note that Intel only charges Apple an additional $75 for the faster CPU ($316 vs. $241), but since the CPU is soldered onto the motherboard you can't swap chips yourself.

If all you care about is the larger cache, the $500 upgrade cost is a tough pill to swallow. Even the increase in drive space isn't all that attractive for the money. The increase in video memory is nice but 256MB should be all you need for smooth Exposé performance on the 15" 1440 x 900 display.

Our recommendation? If you're going to upgrade your notebook in another 1.5 - 2 years anyways, pocket the $500 and don't bother with the added cache. It's not going to do much for you today.

This performance comparison also means that the base MacBook can offer very similar performance to the MacBook Pro, just as you'd expect. The only reasons to buy the Pro are, as we mentioned, mostly feature-based.

Are They Any Faster continued What About Battery Life?
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  • alisonkay2008 - Friday, March 7, 2008 - link

    You can get the best Macbook Pro Case at Macbook Pro Case
  • alisonkay2008 - Friday, March 7, 2008 - link

    Sorry... the link didn't work.
    http://www.macbook-pro-case.com">http://www.macbook-pro-case.com
  • JAS - Tuesday, March 4, 2008 - link

    FWIW, MacWorld Labs is reporting that the new "entry level" MacBook Pro is about 10% faster than the model it replaces.

    http://www.macworld.com/article/132330/2008/03/mac...">http://www.macworld.com/article/132330/2008/03/mac...

    On this third year anniversary of my current laptop, I'm headed over to the Apple Store to purchase the 2.4 gHz model. Thanks to Anand for providing his helpful analysis.
  • brunerd - Tuesday, March 4, 2008 - link

    Quick note about the Exposé key and some modifier keys:
    If you hold down Command when pressing Exposé (F3) it shows Desktop
    If you hold down Control when pressing it, it shows just the App Windows

    So you don't have to resort to fn-f12 or fn-f11 to get the above behavior.

    Thanks for the write up, nice to know it's running cooler.
  • louieking - Tuesday, March 4, 2008 - link

    I was very disappointed that you did not compare the new Penryn 2.6GHz, 200GB- 7200RPM model with the 2007 Merom 2.6GHz, 200GB- 7200RPM model. I don’t think the tests were comparing apples for apples. I think most people interested in your reviews would have wanted to see the difference in overall performance (processing times, battery life) as it relates to lower voltage demands of the Penryn. This would have shown true comparison in battery performance since I suspect that the Penryn version would out-perform in all tests and still have better battery life by a few minutes. Lastly, I think many folks would have been intrigued with a test that showed Firewire 800 download speeds as it relates to battery life. This is an everyday task that would make a difference for a professional MacBook Pro user.

    PS. It’s not too late to WOW the world with your review since you usually beat everyone else to the punch.

    Thanks for your insight.
  • azca - Monday, March 3, 2008 - link

    Hint: you can use a tiny driver/software to control the frequency of the intel cpus to show better comparison in your charts:

    http://www.coolbook.se/CoolBook.html">http://www.coolbook.se/CoolBook.html

    Please, if you can, use this for your next review so that you can have better apple-to-apple comparison.

    You can also use the program to undervolt the cpu and hence measure the thermal output and lifespan of battery etc.

    Thank you.
  • Pete248 - Monday, March 3, 2008 - link

    While the MacBook Pro keyboard isn't bad, I'm really wandering, why Apple didn't switch to the new keyboard they now use in the MacBook, the Air and the external keyboards.
    Having tried both side by side, the new keyboard feels more definite than the MacPro keyboard. And its probably less susceptible to dust, crumbs and water - the later killing the MacBook Pro keyboard easily - even in traces.
    With a new keyboard I would have pulled the trigger for a purchase, now I'm holding back to see what comes within the next 3 months.

  • Wolfpup - Monday, March 3, 2008 - link

    The review says Intel's upcoming video would help the Macbook Pro with Blu Ray playback. Presumably that should have said help the Macbook, as the Pro doesn't use integrated video, and has already had a GPU that accelerates Blu Ray playback for most of a year.

    [quote]MelCarnahan, 2 hours ago
    The author claims Apple picked the right CPU partner in Intel, yet these Intel CPUs could not come close to matching a 32nm Quad Core IBM Cell processor with 2000 MHz FSB. It is disingenuous to compare these Intel egg fryers with a single core PowerPC with a 133MHz FSB. Clearly the Cell processor is superior both in performance and battery life. Only those who wish to use their Yonahs to fry eggs prefer Intel. [/quote]

    Is this some kind of joke? If so, I don't get it. There's so much wrong with this post I don't know where to start, and someone else can do a far better job explaining why, but off the top of my head:

    Cell is a TERRIBLE general purpose CPU. It gets destroyed by Netburst architecture, let alone Intel's modern CPUs. It's great for specific things, but would be terrible for a computer (and is very questionable for a game system for that matter...)

    As far as I know, Intel is a who process ahead of anything Cell is produced on. Geez, the PS3 version is only now hitting 65nm.

    I have no idea why Cell would run COOLER. If anything I'd assume the reverse is true, and certainlly it is anyway because AFAIK there's no 45nm Cell (let alone 32nm as claimed).

    [quote]The Yonah fans sound distinctly like one of those unarmored Humvees with its muffler blown off. The Merom 2.2 Macbook Pro is an improvement but still far hotter, louder and short-batteried compared to the PowerPC. [/quote]

    The Macbook Pro's I've used are dead silent unless they're pushed-but that's a case design issue. I have no idea how they compare to the G4 that was used in terms of the power they use, but I don't think it was much different, and certainly Intel's CPUs would destroy those G4s in terms of power/performance.
  • MelCarnahan - Monday, March 3, 2008 - link

    The author claims Apple picked the right CPU partner in Intel, yet these Intel CPUs could not come close to matching a 32nm Quad Core IBM Cell processor with 2000 MHz FSB. It is disingenuous to compare these Intel egg fryers with a single core PowerPC with a 133MHz FSB. Clearly the Cell processor is superior both in performance and battery life. Only those who wish to use their Yonahs to fry eggs prefer Intel.

    Secondly, Macbook and Macbook Pro keyboards are a disaster. Forget bells and whistles and multitouch. They don't even get the basics right. These are basically what was long derided as cheap chiclet keyboards for many years. The backlighting is frivolous when you consider that even at the dimmest setting, the screen is enough to light up a room. The screen is certainly bright enough to light up both the room and the keyboard. The first and most important requirement of any keyboard is a dedicated, full-size page up and page down key. Second, full-size arrow keys. Even the first TRS-80s got this right and Apple still can't get it right. They could create a feature where you waddle your elbows like a duck while holding up three fingers and bending your knees and then the page scrolls down a page - or they could just include a proper page-up and page-down key.

    The Yonah fans sound distinctly like one of those unarmored Humvees with its muffler blown off. The Merom 2.2 Macbook Pro is an improvement but still far hotter, louder and short-batteried compared to the PowerPC.

    For solutions see: http://www.terrasoftsolutions.com">http://www.terrasoftsolutions.com

  • hernan1304 - Monday, March 3, 2008 - link

    If you want a custom case made specifically for MB Pro or Air, check out vajacases.com - I've had one of their iPod cases for almost two years and it's been great. Very very very expensive and they take a long time to make but they definitely don't look like generic laptop bags and they hold up. Not affiliated with them in any way, by the way.

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