Overclocking G4 DUAL 450MHz

Discussion in 'Mac Basics and Help' started by Sawtooth811, Nov 6, 2007.

  1. macrumors 6502

    Sawtooth811

    Joined:
    Oct 18, 2007
    Location:
    Charleston, IL
    #1
    Give me your opinion:

    Do you think it'll be worth $35.00 to buy a DUAL G4 CPU W/Heatsink, and overclock it to Dual 800MHz? Don't worry, I'm skillful at micro-soldering, and don't post crap like "It won't work", and crap like that, OK?:mad:
     
  2. macrumors 68000

    FJ218700

    Joined:
    Mar 8, 2007
    Location:
    Blue Dot, Red State
    #2
    for $ 35, sure. I upgraded my Sawtooth to dual processors a while back and the difference is breathtaking. Even with the same video card you have in your sig, if you can get the RAM maxed Leopard will run pretty well.
     
  3. thread starter macrumors 6502

    Sawtooth811

    Joined:
    Oct 18, 2007
    Location:
    Charleston, IL
    #3
    Great!! Do you think It'll be as good as a REAL DUAL 800MHz processor (ALONE)?
     
  4. macrumors 68000

    FJ218700

    Joined:
    Mar 8, 2007
    Location:
    Blue Dot, Red State
    #4
    I doubt the processor will last as long overclocked. Also depends on how good you are at soldering.

    PM me if you need some RAM.
     
  5. macrumors regular

    Joined:
    Aug 19, 2002
    Location:
    Boston, MA
    #5
    I think you should post more threads about your G4.
     
  6. macrumors 65816

    SmurfBoxMasta

    #6
    Hope you got some big hefty fans ready to attach to the top or sides of the heatsinks.....that thing is gonna smoke.......literally :eek:

    that's almost a 100 increase in clock speed, so I doubt it will last more than a few months at best :p

    good luck & please post back with progress reports.........
     
  7. macrumors 65816

    CubeHacker

    Joined:
    Apr 22, 2003
    #7
    A Dual 450mhz to 800mhz ? You're dreaming dude. You can probably make 500mhz, and at the very best, 550mhz. Anything over that isn't possible on a 7400 G4.
     
  8. thread starter macrumors 6502

    Sawtooth811

    Joined:
    Oct 18, 2007
    Location:
    Charleston, IL
    #8
    I DID!:D

    Yes it is possible!:mad: REMEMBER: I asked for people NOT to say that It's not gonna work! It IS possible! I'm skilled at this stuff! And I've done this before, successfully!
     
  9. macrumors 6502a

    spinne1

    Joined:
    Mar 12, 2005
    Location:
    Hermitage, TN USA (near Nashville)
    #9
    Since nobody believes it will work, but you KNOW it will work, why don't you enlighten everybody with HOW you do it rather than berate the masses for not being as smart as you are.
     
  10. thread starter macrumors 6502

    Sawtooth811

    Joined:
    Oct 18, 2007
    Location:
    Charleston, IL
    #10
    I didn't say how smart I was, I said how skillful I am!:rolleyes:
    I'm not judging anybody.:cool:

    I'll show you as soon as I receive the CPU.
    There would be a Forum named:

    "G4 DUAL 800 7400"
     
  11. macrumors 6502

    jellomizer

    Joined:
    Sep 12, 2006
    Location:
    Upstate NY
    #11
    Well it seems like you are going to do it anyways. So I guess the question is is $35 a good price for a 450mhz G4 Processor? Yes it would. To clock it up to 800 mhz is kinda immaterial. Will you get a noticeable speed increase is an other question. CPU mhz speed is only one factor and actually a rather minor one. Most of the stuff that really slows a computer down is Cache and Bus speed, and Memory size and Speed...) My Wifes iMac runs faster then my MacBook Pro even though they have the same processor type and speed, she has less ram. But a faster Bus and better video that makes it run a tad faster. If over clocking systems is your hobby then go ahead have a blast. I myself wouldn't do it even if I could do it well. Just because I will only get a marginal speed increase and would send a lot of time I could be doing something else.
     
  12. thread starter macrumors 6502

    Sawtooth811

    Joined:
    Oct 18, 2007
    Location:
    Charleston, IL
    #12
    I knew this stuff already, like the megahertz myth, megahertz doesn't really mean speed, and stuff like that, but when it comes to overclocking, you are correct, bus speed is another factor in CPU speed, because it helps multiply speed. For example, look at my chart below on G4 clock speeds:

    Clock Bus speed Factor

    350MHz 100MHz 3.5x
    400MHz " 4.0x
    450MHz " 4.5x

    e.t.c.

    You get the picture? Bus speeds can help multiply clock speeds!
     
  13. macrumors regular

    Joined:
    Aug 19, 2002
    Location:
    Boston, MA
    #13
    I think what you mean to say is:

    Clock Speed = Bus Speed * MultiplicationFactor
     
  14. macrumors G5

    Consultant

    Joined:
    Jun 27, 2007
    #14
    Why don't you try to over clock your single 450 first.

    If that works, then do it on the dual 450. This way you'll have a working computer, and you either end up with a dual 450 or a dual 800 (or a bit less), instead of ending up with a single 450 if you only try to over clock the dual 450 and something didn't work out.
     
  15. macrumors 68000

    disconap

    Joined:
    Oct 29, 2005
    Location:
    Portland, OR
    #15
    Solid advice there. That's what I always did when messing around with microsoldering; try to improve the cheap one first to make sure it works...
     
  16. thread starter macrumors 6502

    Sawtooth811

    Joined:
    Oct 18, 2007
    Location:
    Charleston, IL
    #16
    Remember, I said I've experienced and done this already.:) I had another single G4 processor, and I UNDERclocked it at 300MHz, so maybe, I have the first G4/300MHz processor!:eek:
     
  17. macrumors member

    Joined:
    Nov 9, 2007
    Location:
    Florence, Arizona
    #17
    Why would you slow down your cpu?


    And underclocking won't strain the cpu, while overclocking will.:apple:

    You may be able to over clock the 450 to 550, but not any higher. They won't run at that speed. MHZ isn't a myth - it's the timing on the clock chip.

    Just putting in the dual chips will speed up your system by at least 75% over what you have now. You are still going to be limited by your buss speed, however. 100mhz is what the buss is clocked at. Plus if you do OC the chips, you want to put bigger heat sinks on. higher MHZ means higher heat.:eek:
     
  18. macrumors 68000

    disconap

    Joined:
    Oct 29, 2005
    Location:
    Portland, OR
    #18
    The bus generally won't cause bottlenecking or noticeable slowing at G4 processors below 1gHz.
     
  19. macrumors 601

    OrangeSVTguy

    Joined:
    Sep 16, 2007
    Location:
    Northeastern Ohio
    #19
    i'd like to overclock my 500mhz dp. do i just bridge the contacts with solder or do i use a resistor?
     
  20. macrumors member

    Joined:
    Nov 9, 2007
    Location:
    Florence, Arizona
    #20
    Well, you can over clock thru the OF Firmware.

    reboot, and hold down the "CMD","OPT","O" +"F" keys.

    enter the NVRAMRC editor (<enter> shows you should press the"return" key)

    nvedit<enter>

    Then type the following script exactly - including the spaces.

    " /" select-dev<enter>
    7efdc44 " clock-frequency" get-my-property 2drop !<enter>
    " /cpus/PowerPC,G4@0" select-dev<return>
    1fca0554 " clock-frequency" get-my-property 2drop !<enter>
    7efdc44 " bus-frequency" get-my-property 2drop !<enter>
    1fbf711 " timebase-frequency" get-my-property 2drop !

    Type ^C (Control + 'C') to exit nvedit
    save the script:

    nvstore<enter>

    enable the NVRAMRC by typing :

    setenv use-nvramrc? true<enter>

    and then reboot to the new time constant by typing

    reset-all<enter>

    This will save stuff you changed and reboot at a new speed.
    Works for my G4 single. Changes from 500 for the CPU speed to 533, and buss speed goes from 100 to 133. About 1% or so.
     
  21. macrumors 601

    OrangeSVTguy

    Joined:
    Sep 16, 2007
    Location:
    Northeastern Ohio
    #21
    wow cool thanks! don't know if i will see a difference but seems to have taken a few seconds off the startup time.
     
  22. macrumors member

    Joined:
    Nov 9, 2007
    Location:
    Florence, Arizona
    #22
    Glad you like it.

    Not sure if you can increase the numbers yet.. still experimenting.

    If you have to do the four-finger-reset (cmd-opt-P-R) it will reset everything back to default, then you have to re-enter it all.

    Have fun!
     
  23. macrumors 68000

    disconap

    Joined:
    Oct 29, 2005
    Location:
    Portland, OR
    #23
    Just so you know, this doesn't actually change the bus or processor rate, it just changes how the system reads it. The system will still operate at the same speed it did before this hack.

    Also, 33 is 33% of 100, and 33 is 6.6% of 500. ;)
     
  24. macrumors 601

    OrangeSVTguy

    Joined:
    Sep 16, 2007
    Location:
    Northeastern Ohio
    #24
    ah, so that whole trick was just playing with my mind huh
     
  25. thread starter macrumors 6502

    Sawtooth811

    Joined:
    Oct 18, 2007
    Location:
    Charleston, IL
    #25
    Guys, I'm NOT going to overclock the DUAL G4 anymore, because I don't feel like buying and waiting for a G4 to ship. Instead, I will buy a G5 Quad Core 2.7GHz next year, NOT a Mac Pro, because the Mac Pro doesn't properly fit my needs like a G5. Plus, the G5 is FASTER in tasks I do.
     

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