Info regarding the 7457

Posted:
in Future Apple Hardware edited January 2014
Apologies if this has already appeared, but macrumors notes that Motorola has posted a PDF with information about the Motorola 7457 which is referred to as the 4th generation of the G4:





http://e-www.motorola.com/files/32bi.../MPC7457EC.pdf
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Comments

  • Reply 1 of 80
  • Reply 2 of 80
    neutrino23neutrino23 Posts: 1,561member
    It looks nice. Supposedly does a little more per clock than the previous version. Lower power requirement. Faster clock. What's not to like?
  • Reply 3 of 80
    wmfwmf Posts: 1,164member
    Not much interesting in there.
  • Reply 4 of 80
    wmfwmf Posts: 1,164member
    Quote:

    Originally posted by neutrino23

    Supposedly does a little more per clock than the previous version.



    The PDF says the microarchitecture is identical. They didn't even fix the 7455's errata.
  • Reply 5 of 80
    powerdocpowerdoc Posts: 8,123member
    Quote:

    Originally posted by wmf

    The PDF says the microarchitecture is identical. They didn't even fix the 7455's errata.



    The larger L2 cache alone, will give a 5% speed boost.

    The faster speed of 1,3 ghz is quite disapointing.

    The chip has 58 M transistors, like the PPC 970. At equal mhz the PPC 970 is faster, at equal transistors the PPC 970 is much faster. It means that the L3 cache is not a good pattern for a desktop chip, it's a waste of transistors : we won't see it in the next generation of PPC 9xx chip. The L3 cache is the wood leg, that Mot gave to his chip, to counterbalance their lame bus. It's a pitty.



    The 7457 is an old design on a new fabbing process.



    This chip will be used by Apple during the one year transition. New powerbook and i mac reaching 1,3 ghz will be showed at Paris. It seems that Mot is dead in the high end PPC market.
  • Reply 6 of 80
    brussellbrussell Posts: 9,812member
    Quote:

    Originally posted by wmf

    The PDF says the microarchitecture is identical. They didn't even fix the 7455's errata.



    Well it does have twice the L2 cache. And it has room for more L3 as well.
  • Reply 7 of 80
    brussellbrussell Posts: 9,812member
    Quote:

    Originally posted by Powerdoc

    The chip has 58 M transistors, like the PPC 970.



    That can't be right.



    [edit]It is right.
  • Reply 8 of 80
    well, sorta...



    the L3 can now accomodate up to 4MB, but only 2MB of which can be used as a cache. The other 2MB is either "unused" or used as "private memory". So it's unlikely Apple would opt for any more than 2MB, and I guess only 1MB for cost reasons.



    Also, unless I'm mistaken, the L3 would not up the transistor count. The L3 is off-die.



    Did anyone else notice the mention at the end of the pdf about a 1.1v (as opposed to 1.3v) 1GHz core? (7457 & 7447) Tell me that wouldn't be nice for the 12"!
  • Reply 9 of 80
    Quote:

    Originally posted by Powerdoc

    The larger L2 cache alone, will give a 5% speed boost.

    The faster speed of 1,3 ghz is quite disapointing.

    The chip has 58 M transistors, like the PPC 970. At equal mhz the PPC 970 is faster, at equal transistors the PPC 970 is much faster. It means that the L3 cache is not a good pattern for a desktop chip, it's a waste of transistors.




    IMHO a 15" 867 Mhz PowerBook with L3 cache is significantly faster than a 12" PowerBook without L3. The L3 is expansive, but it's not a waste of transistors. It's not located on-die. The 1.3 GHz parts are targeted at the embedded market. Remember, the 7455 tops at 1 GHz. Apple will get 1.6 GHz 7457's, but maybe not immediately.
  • Reply 10 of 80
    neutrino23neutrino23 Posts: 1,561member
    Quote:

    Originally posted by Powerdoc



    The 7457 is an old design on a new fabbing process.



    This chip will be used by Apple during the one year transition. New powerbook and i mac reaching 1,3 ghz will be showed at Paris. It seems that Mot is dead in the high end PPC market.




    I don't disagree with you, but until they can make a lower power version of a 970 this is the fastest chip for a laptop.
  • Reply 11 of 80
    omekomek Posts: 43member
    Ya, what if Apple used some of it's own technology to make the Moto chip a little faster.... could happen.... And we can't forget that maybe Apple added a few new features to the updated PBs, to make up for the wait....
  • Reply 12 of 80
    eugeneeugene Posts: 8,254member
    Quote:

    Originally posted by BRussell

    That can't be right.



    Yes it can, because the extra cache requires extra transistors. The figure is from the PDF anyway.
  • Reply 13 of 80
    kupan787kupan787 Posts: 586member
    Quote:

    Originally posted by Gyroscope

    Remember, the 7455 tops at 1 GHz. Apple will get 1.6 GHz 7457's, but maybe not immediately.



    Why do people keep posting this? MOTs own website clearly shows a 1400 MHz part for sale:



    http://e-www.motorola.com/webapp/sps...=01#orderables



    See the 6th item down (XC7455BRX1400PF). So If they are saying 7457 at 1.3GHz, why would you think they secretly have a 1.6 part? MOT announces what they have.



    [edit] Interesting to note, the 1400MHz part has a list price of $507.74. That is on an order of 36 (the lowest quantity they sell). I couldn't find info about volume pricing (the site didn't list it). But does anyone have any ideas on 970 chip costs?
  • Reply 14 of 80
    Quote:

    Originally posted by kupan787

    Why do people keep posting this? MOTs own website clearly shows a 1400 MHz part for sale.



    It was not the case when the 1,42 GHz PowerMac was introduced.



    XC7455BRX1400PF The "P" part is intended for desktops.



    as stated by Motorola...



    Quote:

    The X prefix in a Motorola part number designates a ?Pilot Production Prototype?. These parts have only preliminary reliability and characterization data.



    Quote:

    Originally posted by kupan787

    So If they are saying 7457 at 1.3GHz, why would you think they secretly have a 1.6 part?



    Different voltage, higher power consumption = not for the embedded market.
  • Reply 15 of 80
    powerdocpowerdoc Posts: 8,123member
    Quote:

    Originally posted by neutrino23

    I don't disagree with you, but until they can make a lower power version of a 970 this is the fastest chip for a laptop.



    I don't disagree with you either :

    Quote:

    This chip will be used by Apple during the one year transition. New powerbook and i mac reaching 1,3 ghz will be showed at Paris



    I am just disapointed (but not surprised) of what IBM is able to do with 58 millions transistors, and what IBM is able to do on the same fab process and with the same amount of processors.
  • Reply 16 of 80
    powerdocpowerdoc Posts: 8,123member
    Quote:

    Originally posted by Gyroscope

    IMHO a 15" 867 Mhz PowerBook with L3 cache is significantly faster than a 12" PowerBook without L3. The L3 is expansive, but it's not a waste of transistors. It's not located on-die. The 1.3 GHz parts are targeted at the embedded market. Remember, the 7455 tops at 1 GHz. Apple will get 1.6 GHz 7457's, but maybe not immediately.



    The L3 cache is not a waste of transistor for a 7455 or 7457, i am quite aware of this. But a better front side bus, is more helpful than a L3 cache controller. The L3 controller of the 745x series exist only because the front side bus sucks.



    If you compare a PPC 970 and a 7457 who both have the same L2 cache, the same amount of transistors and the same fabbing process, then you will be astonished by the difference of level of performance. The G5 clock at 2 ghz, a 7457 at 1,3

    At equal mhz:

    - perform equally for altivec

    - better for integer

    - much better for fp calculation.

    With the proper optimization, the G5 will be twice as fast as the 7457, and it will be less expansive at least to fab, due to the lack of L3 memory.
  • Reply 17 of 80
    matsumatsu Posts: 6,558member
    Quote:

    Originally posted by Gyroscope

    IMHO a 15" 867 Mhz PowerBook with L3 cache is significantly faster than a 12" PowerBook without L3. The L3 is expansive, but it's not a waste of transistors. It's not located on-die. The 1.3 GHz parts are targeted at the embedded market. Remember, the 7455 tops at 1 GHz. Apple will get 1.6 GHz 7457's, but maybe not immediately.



    Timed tests do NOT agree with you. This was tested extensively when the PB12 first came out. In timed tests, the PB12 was always between 5-10% of the Ti867.



    This is underwhelming, but I still think you're looking at the next 12 months of Apple (non-tower) products.



    It does however accelerate the pressure to move to G5's.



    I wonder however what the G4 would look like at .09u ?



    And, also, if Moto is still working on anything to supercede it. I think Apple wants to keep them as a supplier. If the offerings don't get better after 12 months, they're only going to be able to employ them in the eMac and iBook. Even the iMac will have to move on.



    What's interesting, if Moto can get a new chip designed, IBM might actually want the fabrication business of that chip. It seems fishkill was designed with that in mind: contract fab work. And, regardless of the past, Apple has a keen interest in keeping a second supplier.



    We'll know in 12 months whether Moto stays or Apple tells them to finally stick it. It's to early yet to write them off.
  • Reply 18 of 80
    maclogicmaclogic Posts: 35member
    Quote:

    Originally posted by Powerdoc

    The G5 clock at 2 ghz, a 7457 at 1,3

    At equal mhz:

    - perform equally for altivec

    - better for integer

    - much better for fp calculation.

    With the proper optimization, the G5 will be twice as fast as the 7457, and it will be less expansive at least to fab, due to the lack of L3 memory.




    Well almost true, the G4 has a better altivec unit tan the 970!

    But in the next iteration of the 970 we migth see a better altivec ...



    And the integer is not that much faster or is it?
  • Reply 19 of 80
    programmerprogrammer Posts: 3,453member
    Quote:

    Originally posted by BRussell

    Quote:

    The chip has 58 M transistors, like the PPC 970.



    That can't be right.



    Oh its right, alright. Apparently its because the G4 is an "all static design", whatever that means. To me it says that IBM managed to get 5+ times as many inflight instructions, more instruction units, a more flexible dispatcher, a much faster bus, a 64-bit PPC implementation, and a bunch of other goodies all for the cost of a G4 with a 512K L2 cache. And at roughly the same clock rate it appears they have roughly the same power consumption (20W @ ~1.3 GHz).



    And this isn't a G4 on a new process, its a G4 on an old process since everybody else has been using 0.13 for a while now.



    The integer and AltiVec units in the G4 might theoretically be more capable, but in practice the 970's flexible dispatch to integer & AltiVec, and the vastly improved FSB and out-of-order-execution, will mean it actually performs quite a bit better.
  • Reply 20 of 80
    jousterjouster Posts: 460member
    Programmer, I think that's the most scathing post I've ever seen from you!



    Mind you, when you point out the contrasts between the two procs, it's not hard to see why..........
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