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Power mac g4 processor upgrade

Discussion in 'PowerPC Macs' started by meezvzw, Jun 25, 2009.

  1. macrumors newbie

    I have a power mac g4 (Power Mac G4 350Mhz (Yikes, PCI graphics) (M7826LL/A) And i want to upgrade its processor to a 1.0 ghz can someone tell me where to buy one... or if i even can
  2. macrumors 6502

    Dave H

    It's probably more cost effective to get a newer AGP based G4, which would have fewer bottlenecks.
    PCI cards and drives (and maybe RAM) would be transferable to the newer machine.
    With that said, the fastest upgrade ever made for your Mac was a 1.1GHz G3.
    As explained in the link, G4 upgrades of 700MHz and up will slow down the system bus in a Yikes G4 or a B&W G3.
    G4 upgrades of 650MHz or lower can use the full bus speed since they use an earlier and more compatible model of G4 chip.
  3. macrumors 68040


  4. macrumors 603

    What OS are you gonna run on that little vixen?
  5. macrumors 6502

    Dave H

    Good point.
    On a Yikes, you would need software that enables speeds above 800MHz.
    There are two options for that.
    This one is free, but only works with OS 10.4.9 or lower.

    This one is $12.95, and supports OS 10.4.11, but only supports CPU speed setting on G3s of 800MHz or higher, not on G4s.
    It also supports OS 9 if that's of interest.
  6. macrumors newbie

    The thing is, is that I'm coming from a windows xp comp. So im really new at the whole mac thing. It has 10.3 Panther on it with an upgraded 512 MB ram... I want to upgrade it to 10.5 leopard But it needs a faster processor. And i just don't have the funds to buy a Mac Pro. The only reason i have this one is that a friend got a Macbook and did not need it any more. Today i put in a secondary hard drive so that i had enough room for 10.5. My budget is $300 subtract $100 or so for 10.5.

    Thank you so much for your reply :D
  7. macrumors 65816


    I think uyou may run into some problems on Open Firmware.

    If I recall, one can circumvent the minimum requirments as given by 10.5 by modifying Open Firmware, but this is a "Dial 'M' for 'Mundane'" task - very daunting. Using the 1.1GHz G3 processor, methinks, would not run 10.5 without modding - probably having to do with the vector processor. :( Check around, I could be very wrong - people on OSX86 know about this more then I do, and a google search would do wonders as well.
  8. macrumors 603

    From Low End Mac:

    To install Leopard on an "unsupported" G4 clocked under 867 MHz:

    1. Reboot your Mac and hold down the Cmd-Opt-O-F keys until you get a white screen with black text. This is the Open Firmware prompt.

    2. Insert the Mac OS X Leopard Install DVD.

    3. Type the following lines exactly as shown below into the Open Firmware prompt. Be mindful of capitalization, spaces, zeros, etc. If the command is properly typed and understood, Open Firmware will display "ok" at the end of each line after you hit "return". What these lines do is set the CPU speed reported by Open Firmware to OS X as an 867 MHz G4 processor system. They then continue the boot from the DVD drive.

    For single CPUs, use the following three lines:

    dev /cpus/PowerPC,G4@0
    d# 867000000 encode-int " clock-frequency" property
    boot cd:,\\:tbxi
    For dual CPUs, use the following five lines:

    dev /cpus/PowerPC,G4@0
    d# 867000000 encode-int " clock-frequency" property
    dev /cpus/PowerPC,G4@1
    d# 867000000 encode-int " clock-frequency" property
    boot cd:,\\:tbxi
    4. Continue the install normally.

    5. This CPU setting is only in effect until the Mac reboots. Once OS X Leopard is installed and your Mac has rebooted, the proper CPU speed should once again be displayed when you select About This Mac under the Apple menu.

    UPDATE: The folks at iCode have taken the information from this article and used it to create LeopardAssist, a free program that automates this process and eliminates the need to fiddle with OpenFirware on your own.

    LEM Editor's note: Some readers have noted problems booting the Leopard install disc using the above commands. If so, substitute "mac-boot" (without the quote marks) for the last line in the above Open Firmware commands. Also, if your Mac locks up hard during this process, resetting the PRAM (start your Mac and immediately hold down Cmd-Opt-P-R until your Mac restarts) should bring it back to life.


    I have used this method many times, it's really easy and works.

    If you get Leopard up and running on that machine, post about it. I will hook you up with a Graphics Card, gratis. I have an Nvidia 6200 in PCI form which works a treat in MOST Macs with PCI slots, but I have never tested it in a Pre-AGP Mac.

    Years back I had a Blue & White and slapped a G4 ZIF from a Yikes in it. I was trying to build up a system to edit my reel with. Trying to fire up FInal Cut I ran into a little problem with my Rage 128. And thus began my Video Card hobby.

    So, I still have a warm place in my heart for such a machine.
  9. macrumors 65816


    Thanks Rominator - I was going to edit in two links to the discussion, a Guide on MR and a guide on MacMod; however, your information is infinetly more simple.

    However, the OpenFirmware input - its telling the source file that the OSX installer reads that the processor IS the minimum? And would this change if one was using, say, the 1.1GHz G3 that was linked earlier?
  10. macrumors 6502

    Dave H

  11. macrumors newbie

    So even if i put a new processor in it, It wont work? ill need to do this "Open firmware thing? Will the new processor at least make it process faster?
  12. macrumors 6502

    Dave H

    A G4 processor upgrade can work with Leopard.

    Not sure about a G3 processor on Leopard though.
  13. macrumors 65816


    Processes will be faster - I'll search around. You could potentially add MORE bottlenecks to your systems with a speedy upgrade - the processor may downclock the FSB. :eek: Meaning that computationaly-intensive applications may run better, but memory-intensive ones will act even more choked up. All depends on whatever procssor you can upgrade to.

    Personally, I would stick to the G4 processors instead of a higher-clocked G3 upgrade. I'll do some research - the G4 processor upgrades may not downclock the FSB.
  14. macrumors newbie

    Thanks anyway, But i found one That should work. =)
  15. macrumors newbie

    Thank you! I will do this "open Firmware" Thing... Also i have found a processor and will order it ASAP (Need funds soon). Its 1.0 Ghz just as i wanted. I will be certain to let you know when i get OS X 10.5 up and running... Also i have an hp keyboard... Do i need to buy an apple one for this to work??
  16. macrumors 6502

    Dave H

    If it's the Sonnet G4 1GHz, there is a firmware update for it.
    Encore Firmware Updater Installer
    The firmware update might need to be installed before the original processor is removed.
  17. macrumors 65816


    Nope! If I can remember correctly, the Windows key is the command key.
  18. macrumors P6

    Tallest Skil

    No, that's Control. The Windows key exists because of licensing. It doesn't really do anything.

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