New Powerbooks' Processor: overclocked, or PPC 7455?

Discussion in 'Macintosh Computers' started by BigDawgES, Apr 19, 2004.

  1. macrumors member

    BigDawgES

    Joined:
    Mar 31, 2003
    #1
    The following article questions whether Apple will stick their more advanced G4 chip (PPC 7455) into the latest PowerBooks revision or simply overclock their older PPC 7447.

    http://www.insanely-great.com/news.php?id=3317

    I'd be grateful if anyone can find out which one apple chose to use in today's PM revision.
     
  2. macrumors G3

    Joined:
    Jul 23, 2002
    Location:
    Sol III - Terra
    #2
    How about the 7447A?

    And it's not overclocked.

    And in the article you posted the link for? The Ti 800MHz Probably beat the 12" 867MHz due to a faster system bus, not due to the difference in cache.

    Apple has never sold a system with an overclocked processor.
     
  3. Moderator emeritus

    Mr. Anderson

    Joined:
    Nov 1, 2001
    Location:
    VA
    #3
    where did you find that?

    D
     
  4. macrumors G3

    Joined:
    Jul 23, 2002
    Location:
    Sol III - Terra
    #4
    I found it here - excerpt:
     
  5. macrumors 68040

    CrackedButter

    Joined:
    Jan 15, 2003
    Location:
    51st State of America
    #5
    cough *powermac G4 1.42's* cough cough

    But they do sell mac with UNDER clocked processors ;)
     
  6. macrumors G3

    Joined:
    Jul 23, 2002
    Location:
    Sol III - Terra
    #6
    They were not overclocked. The chips were rated for 1.42GHz by Motorola.

    As for underclocked... actually there is usually a range of speeds a given processor can run at. So they wouldn't be underclocked either. They would just be clocked at a slower certified speed. [The range of speeds only applies to some processor models from some chip manufacturers.]
     
  7. macrumors regular

    Joined:
    Apr 21, 2003
    Location:
    Planet Earth
    #7
    So there!

    So there!

    Always a pedantic person in every crowd.
     
  8. macrumors G5

    Sun Baked

    Joined:
    May 19, 2002
    #8
    The 7445/55 is a LARGER process version of the 7447/57.

    At least the most recent version of the 7455 (there were quite a few as Motorola baby stepped to the 7457s).

    The smaller process allowed them to add a bigger cache within the same space, and you'd probably say the 7457s are the more advanced chips right now (and they do support the L3 cache, in fact they support more than the 7455.)

    Now Apple didn't include the 7457 in the current crop and elected to go with the 7447 (one without the L3 cache) because the 7447 was as fast as the 7455 with L3 cache -- and putting fast L3 cache with the 7457 would be more expensive.

    Plus there might have been issues with the 7457s L3 cache. :rolleyes:

    ---

    Anyways the 7447s have (512K SRAM on-chip L2 cache) and are supposed to be less expensive than the 7445s and probably quite a bit less than a 7455 with a lot of L3 cache.

    So it would be a little strange to choose a hotter, bigger, more expensive solution (7455 with L3 cache) than one as fast or faster that's smaller, cooler, and less expensive.
     
  9. macrumors 603

    aswitcher

    Joined:
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    Location:
    Canberra OZ
    #9

    I hope its this newer chip 7447 with better power management.
     
  10. macrumors G5

    Sun Baked

    Joined:
    May 19, 2002
    #10
    Looking at the MC7447A Rev 1.1/1.1.1 Qualification Report (pdf) I'd almost be able to say, "Yes they are 7447As."

    Since the spec for the 1.33 and 1.5GHz chips are usually the ones Apple's used in the portables in the past -- the W spec series.

    But I also haven't seen a part number for laptops since they swith from the XC74... to the newer part numbering scheme MC74...
     

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  11. macrumors 603

    Dont Hurt Me

    Joined:
    Dec 21, 2002
    Location:
    Yahooville S.C.
    #11
    No more L3? interesting isnt it, Owc Merc Extreme is a 7457 with 2 mb of L3 and i have been pretty happy with this thing. almost a year old. throwing that in the quicksilver was a good move. still thought we would have seen more advancement but moto got it going faster then the 1.42(ahem overclocked G4 hence wind tunnel, massive sinks yada yada yada.) way to go moto took more then a year to squeeze-ever so slowly -.60 mhz?? and the G5 ?will it be a year before rev B?? man Apple is taking such a long time to update stuff and then when its updated they remove all L3 from G4. The CPU situation at Apple is kind of rotting. no progress at all on the CPU front.
     
  12. macrumors 65816

    yamabushi

    Joined:
    Oct 6, 2003
    #12
    I think that the new Powerbooks probably do use the 7447A. These are not in the same league as the 970 and 970fx but it is good to see an updated moto proc anyways.

    Well the G4 clock speed improvements have shown progress. A couple of years late but better late than never. The recent bumps are really pretty good in my opinion.

    Here is a summary of the increase in clock speed from previous top end verions of various models: eMac +25%, 12"PB +33%, 15"PB +20%, 17"PB +13%.

    I find the fact that less expensive models had a larger percentage improvement to be a very positive sign. I would like to think that this could mean the beginning of a trend towards less crippling of the low end.
     
  13. macrumors member

    Joined:
    Feb 10, 2004
    Location:
    Toronto, Ontario
    #13
    When will people understand that Apple has no need to "overclock" its chips. "Overclocking" implies that one is over-riding the set factory clock multiplier or FSB. Since Apple can set these themselves, they have no need to overclock. A chip is as fast as it can be run without becoming unstable.
     
  14. macrumors 68000

    ZildjianKX

    Joined:
    May 18, 2003
    #14
    Well, the term is used rather loosly here, implying that Apple is selling the same chip rated for the same clock speeds, but simply charging more for the same thing running at a different effective clock speed.
     
  15. macrumors member

    Joined:
    Feb 10, 2004
    Location:
    Toronto, Ontario
    #15
    Well, the same is done by any CPU manufacturer. That is why it is possible to take a P4 2.4C chip and have it run stable at 3.4+GHz.
     

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