Results 1 to 5 of 5
  1. #1


    Member Since
    Jul 13, 2008
    Posts
    1
    Question AGP G4 processor upgrade?
    Hullo,

    I've got a slightly aging AGP G4 running a 400mhz processor.

    I just bought from ebay for a tiny amount of money a 733mhz G4 processor taken from a quicksilver.

    Initially my slightly non technical brain thought this would be easy and definitely work, but now I'm wondering if it now might actually break everything?

    Anyone of you wise people able to let me know?

    ta

  2. #2


    Member Since
    Nov 06, 2007
    Location
    Atlanta
    Posts
    142
    the AGP or "sawtooth" models has a 100mhz bus speed, the quicksilver has a 133mhz bus speed. If it doesn't work it will come up and with errors or dont boot up at all. Im not sure if the 133mhz g4 is backwards compatible. If it is and it still doesn't work try updating the firmware, you will need a os 9.x install in order to update it. Which can be very expensive off of ebay, unless you know someone who knows someone. also make sure you get the install disk not the upgrade disk, it can be very deceiving. One more thing, i dont beleive the QS G4 is going to fit properly, you may have to desolder the pata connector on the edge of the motherboard and be short 2 ide devices. My best guess and it was also my choice when i upgraded my old sawtooth is to buy a upgrade G4 daughter card off of ebay, if you search and search and keep watch you can usually find someone whos selling a upgrade for little to nothing some times. or you can buy a dual 550mhz G4 duaghter card for about 60 bucks off of ebay also, which would be faster than a 733. Also look at fastmac daughter cards they're made for the sawtooth/gigabite models you can buy one brand spank'n new at 1.5ghz for $250 and you can usually find them on ebay from $60-$150 i sold mine a few months back for $133 after shipping. Good luck
    "Stick your head through the portal as it starts to expire and you will have contributed to the worlds first arcane guillotine!"

  3. #3

    harryb2448's Avatar
    Member Since
    Nov 28, 2007
    Location
    Nambucca Heads Australia
    Posts
    22,089
    Specs:
    Imac 27" Retina 5K, 512GB flash memory, 3.3GHz, 16GB memory, macOS Sierra beta.
    Will not work as they are completely different. Best bet is a CPU upgrade similar to what OWC and Sonnet sell. Go to OWC at www.macsales.com and look over their CPU upgrades, which will include the Sonnet. Once you have new prices then look at eBay etc. Look for CPU upgrades with the 2MB L3 cache as they are really fast and anything over 1GHz will handle Leopard no problems.

    Have used the Mercury Extreme upgrades and they have the advantage of adjustable jumper settings for both 100 and 133MHz bus speeds.

    The fastest standard processor you G4 will handle will be a 500MHz DP from a Gigabit Ethernet.

  4. #4


    Member Since
    Nov 06, 2007
    Location
    Atlanta
    Posts
    142
    Yeah sorry, it was a typo, they didn't even make a 550mhz G4.
    "Stick your head through the portal as it starts to expire and you will have contributed to the worlds first arcane guillotine!"

  5. #5


    Member Since
    Jun 19, 2008
    Posts
    16
    It depends on your level of technical skill. If you do a 12V mod on the processor card it will run the quicksilver processor. As mentioned above, you will lose your PATA33 connector, so you would need a PATA PCI card to run your DVD.

    CPU speed x bus speed times clock multiplier. Your 733 runs at 133x5.5=733. So at a 100 Mhz FSB, it will run at 550 mhz 100 x 5.5=550.

    There are some unreliable modifications to attempt to run 133 Mhz. They seem a bit flaky and clearly depend on whether the memory is PC133 or not as well. The easiest way to handle this hurdle is modify the quicksilver module so that it will run at a 7x or 7.5x multiplier. This involves surface mount resistor modifications. See my thread from a few days ago for more details on that. It doesn't have to be done with dipswitches. I am sure that you can just permanently modify it to 750 Mhz with less difficulty.
    mod: I screwed up my user name. Please change it to drjaymez.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Quicksilver processor in AGP power mac g4?
    By zurr in forum Apple Desktops
    Replies: 4
    Last Post: 08-17-2010, 07:18 PM
  2. G4 AGP CPU Upgrade?
    By MontroseGeek in forum Apple Desktops
    Replies: 2
    Last Post: 01-25-2009, 11:40 PM
  3. DVD RW Upgrade (AGP Graphics)
    By t_a_o in forum Apple Desktops
    Replies: 0
    Last Post: 08-21-2006, 11:28 AM
  4. Powermac G4 AGP Graphics Upgrade Question
    By Jonnyfive in forum Movies and Video
    Replies: 0
    Last Post: 08-03-2006, 04:18 PM
  5. powermac g4 (agp) upgrade questions
    By MAC1av3lli in forum Apple Desktops
    Replies: 4
    Last Post: 10-19-2005, 11:31 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •