G5 Processor upgrade for G4s?

Discussion in 'Macintosh Computers' started by leekohler, Jan 21, 2005.

  1. macrumors G5

    leekohler

    Joined:
    Dec 22, 2004
    Location:
    Chicago, Illinois
    #1
    Does anyone know if Sonnet (or anyone else) will ever make a G5 processor upgrade for G4s? It seems to me that if they were, they would have done so by now. Is it a 32/64-bit issue or maybe a bus speed issue?
     
  2. Moderator emeritus

    robbieduncan

    Joined:
    Jul 24, 2002
    Location:
    London
    #2
    This was discussed to death when the G5 was announced. The bus is a major sticking point (not just speed, it talks a whole different language between the CPU and the northbridge). Also the memory bandwidth of a G4 (which is limited by the G4 north bridge) would really slow down a G5 chip.

    Basically it's probably not worth it. I'd hold out for a dual-core G4 upgrade somtime in 2006 (maybe even a dual dual-core upgrade?)
     
  3. macrumors 65816

    blackfox

    Joined:
    Feb 18, 2003
    Location:
    PDX
    #3
    I am no tech genius, but there would seem to be a basic motherboard-design incompatability I would imagine.
     
  4. thread starter macrumors G5

    leekohler

    Joined:
    Dec 22, 2004
    Location:
    Chicago, Illinois
    #4
    Well-Sonnet already makes a dual processor G4 upgrade. It's pricey though-about $600 I believe. I'd buy a Mac Mini before I'd do that. I was just asking because I need to upgrade my Sawtooth desktop and didn't want to get another G4 processor if a G5 might be a possibility. Thanks-you guys answered my question.
     
  5. macrumors G4

    Lord Blackadder

    Joined:
    May 7, 2004
    Location:
    Sod off
    #5
    Too bad I wasn't around, I've wondered the same thing myself. I'll have to go search for the thread...

    To the original poster:

    Beyond technical issues that I don' understand, I think a G5 upgrade is unlikely because the G4 is still a living design offering competitive performance. The G5 doesn't offer enough inherent advantage in the chip alone to make useful on a G4 motherboard, just higher clock really. can you say strangled by the bus?

    What you MAY see at some point (besides higher and higher clocked G4s) are dual-core or twin dual-core G4(2x G4s with dual cores - a tongue twister) upgrade solutions. And honestly, those will be overkill for the Powermac G4's architecture. Its' like putting a 500MHz G3 in a Powermac 6100: you can buy the kit, but you're really wasting the G3 becuse the mobo architecture is too old.
     
  6. macrumors G5

    Sun Baked

    Joined:
    May 19, 2002
    #6
    You might as we bite the bullet and wire an IBM PPC970 Blade into a PCI slot, much easier.

    The G5 requires both the CPU and the Memory controller, along with a small processor or chip -- just to initialize. You almost have a complete computer (without i/o) at that point.

    And you can't plug that into a 60x FSB.

    It would end up being a co-processor card, or something with an HT to 60x bridge chip.

    Almost like buying a z06 vette and updating the computer to limit in it Pontiac Grand Am performance.
     

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