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G4 PPC7447 vs YONAH (place your bets)

Discussion in 'Macintosh Computers' started by minimax, Dec 2, 2005.

  1. macrumors 6502

    Ok, as the Intellification of Macintosh is almost upon us I thought it would be fun to make some predictions on how the G4+ holds up against the Yonah. First benchmarks have been released on Anandtech which show the Yonah performing almost on par with the Athlon 64.
    Let's hope there will be proper applications (PS!) and benchmark tools for OSx86 released together with the introduction of the Macintel.

    My estimation, based on a few benchmarks (also crossplatform) is that Yonah (single core, 2MB L2) will be about 25% faster on IPC.
    I also think that this will be fairly even distributed on FP and integer operations, as Yonah seems to be stronger in integer like the G4.
    With vector instructions the G4 will still be a bit stronger me thinks.
  2. macrumors 603

    Dont Hurt Me

    Me thinks you have been burning some, how about sharing? G4 stronger then Athlon 64 thats funny, or G4 stronger then Yonah LOL.
  3. macrumors 68000

    There is no way the G4 will be stronger than Intel's Yonah. Yonah is going to blow the G4 out of the water, and give the G5 a run for its money.

    Apple will not put in a processor that is less powerful than their current lineup.
  4. macrumors 6502

    If both of you read more careful you would have seen I said stronger on *Vector* performance. It is widely known the Altivec instruction engines are stronger as their SSE1/2/3 counterparts. But Vector instructions are only a part of the total palette and like I said, overall the Yonah will be stronger indeed.

    edit: As I have the idea both of you totally misunderstood what i was saying: IPC = Instructions Per Cycle used as a measure of overall performance relative to the clockspeed. Technically this is not correct as benchmarks can only show system performance per cycle.
    With 'even distributed' I meant both are stronger on integer whereas the G5 and Athlon 64 are relatively stronger on FP operations. So i was not saying the G4 will be as fast as the Yonah, but that the performance difference between both will be fairly even distributed over the spectrum.
  5. macrumors 65816


    Since we are predicting the future ...
    How would a G4 compete if they (Freescale) moved the memory controller on chip? i.e. decrease memory latency and increase bandwidth.
  6. macrumors 604


    I'd be more interested in comparing Yonah to the e600 G4. We're talking about the next gen, scales-to-2-GHz, 64-bit, dual-core, low-power G4's. :)
  7. macrumors 601


    Onboard memory controller does not increase bandwidth.
  8. macrumors 6502

    Onboard memory does increase bandwidth, gives full bandwidth of ram to the CPU and takes load off the FSB.
  9. macrumors 601


    But ram still runs at the same rated speed.
  10. macrumors 6502

    Latency is really important, ondie memory controller means the CPU doesn't have to do nothing while waiting for the memory as often.
  11. Moderator emeritus

    Of course, the AltiVec performance is quite good. It should be--it takes up more of the die than it should--at the expense of double precision floating point math.

    Considering the number of AltiVec-enabled applications vs. those which require strong floating point performance, AltiVec won't matter, except in extreme cases like the PPC-optimised version of BLAST.
  12. macrumors 65816


    Yeah, and since the FSB bus is limited to 200 MHz in the G4 with the memory controller located off chip, the current G4's are unable to take advantage of that speed.
  13. macrumors 65816


    It DOES increase bandwidth and decreases latency!
    RAM bandwidth is about 3.2 gigabytes per second for single channel 400 MHz DDR. G4 FSB at 200 MHz is I think 800 megabytes per second. No point going with dual channel on a "standard" G4. Kind of like sucking a 10 pin bowling ball through a garden hose :eek:
    For more info.

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