Power Mac G3 B&W G4 ZIF upgrade issue

Discussion in 'PowerPC Macs' started by LarsG5, Feb 7, 2017.

  1. LarsG5 macrumors member

    LarsG5

    Joined:
    Aug 10, 2016
    #1
    Hello,
    I have a problem. I've got a B&W G3 and I've heard it's possible to swap the CPU with PM G4 Yikes!. So, few weeks later I've purchased the latter one, swapped CPUs, powered my B&W on and... does't work, I get 5 beeps and that's all.

    I've made some research and as far as I know I need to patch the Boot ROM / Firmware on my B&W to make the G4 CPU work. But... Google knows nothing. B&W's Firmware version is 1.1 and I've got no idea how to patch/downgrade it.

    Have any of you upgraded your B&W with G4 Yikes! CPU successfully? Could you tell me what to do, please?
     
  2. bunnspecial macrumors 603

    bunnspecial

    Joined:
    May 3, 2014
    Location:
    Kentucky
    #2
    I've actually not used a Yikes! CPU in a B&W, but have done a handful of G4 CPU upgrades in them. Somewhere in the OS 9 upgrade sequence(I think maybe 9.1 working from memory) the installer will update the firmware. The practical effect of this update is to lock out G4 compatibility on the logic board.

    I've always used the utility for the specific upgrade I had, but I suspect that the Sonnet patch tool would work for you. It certainly can't hurt anything! If it doesn't work, I'll image my FastMac disk and post it to the Garden(I might have already done that).

    In the mean time, though, try this from Sonnet. You'll need to reinstall your old CPU before running it.

    http://www.sonnettech.com/support/kb/kb.php?cat=317&expand=_a3_a2&action=a1#a1
     
  3. LarsG5 thread starter macrumors member

    LarsG5

    Joined:
    Aug 10, 2016
    #3
    Thanks for your reply!
    I've already tried this one and nope, everytime it ends up with an error saying it cannot find the ROM :(
     
  4. LarsG5 thread starter macrumors member

    LarsG5

    Joined:
    Aug 10, 2016
  5. MikeatOSX macrumors regular

    MikeatOSX

    Joined:
    Mar 26, 2007
    Location:
    Austria
    #6
    Quote:
"You MUST install the Sonnet software before installing your ZIF 
regardless of which OS is installed in your system. The 
Crescendo/Encore/ZIF G4 software installer installs a Power Macintosh 
G3 firmware patch that is critical to the operation of the processor 
upgrade card in your system; without the patch, it won't work. The 
software installer must be run under OS 8.x or 9.x. NOT Mac OS X nor 
Classoc Mode under OS X. One the Sonnet installation is complete, 
you may use any compatible Mac OS, including OS X."
    (quoted form the manual for the Encore/Zif upgrade.)
    http://www.xlr8yourmac.com/g3CARDS/G3_1.1GHz_vs_G4_1GHz_review/index5.html
    http://www.sonnettech.com/support/kb/kb.php?cat=319&expand=_a3_a1_a13_a2_b73_b307_b154&action=b231
     
  6. LarsG5 thread starter macrumors member

    LarsG5

    Joined:
    Aug 10, 2016
    #7
  7. reddrag0n macrumors 6502

    reddrag0n

    Joined:
    Oct 1, 2007
    Location:
    Canada
    #8
    I though all the G3 units had that funky long jumper block that needed to be modified? I know way back when Sonnet said that their higher speed CPU's would only run at 66MHz FSB with the block because the machines couldn't handle them at 100MHz
     
  8. bunnspecial macrumors 603

    bunnspecial

    Joined:
    May 3, 2014
    Location:
    Kentucky
    #9
    The block can be removed and replaced by individual jumpers to set the bus speed and multiplier. The jumpers are "mini" sized or what are common called "SCSI jumpers" since they're the size usually used to set IDs and other settings on SCSI drives.

    Moderate speed Sonnets can run with a 100mhz FSB and Sonnet pulled some magic to avoid having to change jumpers. I know that when I dropped my 500mhz G4 into my AIO, it just reported the right speed and I didn't have to do anything. I'd been running a Yikes! CPU but I think had it clocked at 266 as I was having some other system issues that I was trying to iron out. I dropped the Sonnet in and everything was just perfect.

    With that said, I have run G4s at 500mhz(3rd party, non-Sonnet) in B&Ws and done nothing but change the multiplier. I've also run B&W G3s at brisk speeds(I think I have one at 433mhz now) in beiges without any trouble.

    The high speed ones do indeed require dropping the bus speed on B&Ws. I have a 1ghz, although it's in a beige and I didn't install it so I don't recall what-if anything-was done to the jumpers. If I haven't mentioned it in my rambling(and you didn't know) beige G3s have a 66mhz FSB.
     

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