Power Consumption and Performance per Watt

Compared to the G5, Intel's Core Duo has no problems offering lower power consumption, but what about when pitted against the G4? The whole reason the G4 was kept in Apple's notebook lines was because of its low power consumption; while the Core Duo can easily be a better mobile CPU than the power hungry desktop G5, how does it compare to an already low power G4?

First off, I measured idle power consumption of the entire notebook at the wall outlet. The battery was removed from both notebooks so we're only testing the power consumption of the computer + display.

Total System Power Consumption at Idle

At idle, the PowerBook G4 running at 1.5GHz manages to come in at 21W total system power consumption, a full 3 Watts lower than the Core Duo 2.0GHz system. The number of variables between the two systems are really too many to count, thus making it difficult to declare this a clear victory for the G4 processor over Core Duo, but it does mean that the older PowerBook G4 notebooks consumes slightly less power as a whole at idle than the newer MacBook Pros.

Next, we ran our QuickTime H.264 encode test and looked at peak power consumption under full CPU load. Keep in mind that QuickTime's H.264 encoder is multi-threaded so both cores are under full load in the MacBook Pro:

Total System Power Consumption under Load (Quicktime H.264)

Under full load the PowerBook G4 jumps up to 40W while the MacBook Pro falls 3W short and peaks at 37W, giving us a role reversal. It looks like although the older G4 systems consume less power at idle, the MacBook Pro is greener under full load. Of course low power consumption itself is meaningless if you don't have the performance to back it up (remember Transmeta?). Now let's look at the performance per Watt in the previous test.

What I did for this graph was take the average frame rate during the H.264 encode task and divided it by the peak power consumption during the test thus giving us performance measured in frames encoded per second, per Watt.

Performance per Watt - Quicktime H.264 Encoding

Using QuickTime's H.264 encoder as our benchmark, the new MacBook Pro offers around 62% better performance per Watt than the previous PowerMac G4. For a notebook, that sort of increase in performance per watt is extremely important.

Interestingly enough, despite the relatively similar power consumption characteristics the new MacBook Pro uses a noticeably larger AC adapter than the PowerMac G4 rated at 85W instead of 65W.

Inside the MacBook Pro Performance Comparison: G4 vs. Core Duo
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  • boinkle - Thursday, April 13, 2006 - link

    Great review, apart from making me think "that's still quite pretty!", at the end of the day it's just a PC in an Apple enclosure. It's shiny, fast, but has all the problems of an Apple 1st gen product, with few of the benefits of Core duo showing up...

    How I wish someone had given Freescale some incentive to develop the G4 further (to a reasonablt timescale). It's amazing that it's still even *reasonably* competitive. Imagine dual-core, 65nm G4 derivative production? Don't TI have a 65nm fab up and running now? That's where your 5 hours would come from, Anand... pie in the sky, I know.

    *sigh*
  • littlebitstrouds - Thursday, April 13, 2006 - link

    How about some gaming benchmarks. If you run windows and game are you getting good performance numbers? If I could have a Mac for everyday use and boot up windows when I want to game I might jump on this.
  • Visual - Thursday, April 13, 2006 - link

    you have some borked page 18 after the "final thoughts" page showing up in the dropdown.
    in printarticle.aspx it shows up as a duplicate of page 17 for some reason

    as to the article itself - good job :)
    my guess as to why the vm is faster than the real thing is because the hdd emulation works somewhat like a ramdrive - its a file on the apple hdd but it probably gets cached up by osx or by the vmsoftware itself.
  • plinden - Thursday, April 13, 2006 - link

    quote:

    my guess as to why the vm is faster than the real thing is because the hdd emulation works somewhat like a ramdrive - its a file on the apple hdd but it probably gets cached up by osx or by the vmsoftware itself.


    That could be - I have maxed out at 2GB RAM in my iMac, and I get wired RAM is close to the max and a hefty number of Page Outs (up to 210,000 last time I looked. before it setayed below 5000 even after being on for a week) while running Parallels VM.
  • ibisbowti - Thursday, April 13, 2006 - link

    I been using the 1.83 Core Duo for about a week now. I think it is one of the latest builds according to the serial number. No problems at all, other than it does get pretty warm. Heat issue seems better after latest firmware update. I think the aluminum is designed to be a big heat sink! I thought the Front Row software would be a little gimmicky, but it is pretty cool, especially when sitting the unit on a coffee table and watching the HD movie trailers, IPhoto pics, etc with others. It's an awesome machine so far.
  • artifex - Thursday, April 13, 2006 - link

    Since you say you ran the same tests as in your earlier review, I'd like to see graphs comparing the results of the Intel iMac vs. the MBP. and add in ones for the Intel Mini, if you can. I suspect we'll see iMac > MBP > Mini, but it would be nice to be sure.

    Also, if you could slap Parallels on the Mini and tell us how much of a hit the virtualization takes because the hardware virtualization is disabled for that line, that would be really interesting.

    Thanks.
  • AppaYipYip - Thursday, April 13, 2006 - link

    "Apple quality control at it's best"

    That comment bothers me. Overall, there are no other manufacturers that come even close to Apples quality, design, and workmanship. Yet, you find one key that sits slightly off and suddenly feel the need to make such a blanket statement. If it bothers you so much, take it back and Apple will repair it for you, in record time.
  • Calin - Thursday, April 13, 2006 - link

    The IBM thinkpads (before the Lenovo deal) were regarded as the best business laptops (or at least PC laptops) as quality and workmanship. Too bad they were designed with cramped keyboards (at least the models I saw) and no trackpad.
  • Ryan Norton - Thursday, April 13, 2006 - link

    I'm a PC guy but I like Macs a lot and will probably buy a Macbook Pro, either now or when Merom ones come out. I figure Anand probably is too. Yet I work with Mac zealots who give me endless shit about the unequivocal superiority of Apple everything over PC (except for games, which they concede). So when someone like me finds a glaring flaw that seems like something that should have been spotted before it got to the end user, it's easy to take a cheap shot at Jobs =^)
  • Sunrise089 - Thursday, April 13, 2006 - link

    If I had my dream review of this product, here's how I would have you test gaming performance:

    Test performance in Windows mode. Then compare it to other Core Duo notebooks. Then see if there is any game written natively for OS-X under Core Duo, and run the OS-X version and the Windows version to see the difference in OS on performance on the same machine.

    Other than no gaming info, terrific review.

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