3 Replies Latest reply: Sep 24, 2012 7:27 PM by nOmada
nOmada Level 2 (175 points)

I'm trying to boot from a Mac OS 9.1 CD on a Power Mac 7600 I'm trying to bring back to life

but it appears the blinking question mark. I've tried using the "C" command but it simply doesn't boot.


Any ideas?


Thanks for any help

iBook, Mac OS X (10.5.8), 1.33 GHz/ 1,25 GB RAM/ 320 GB HD/ 00 GB HD FW
  • Allan Jones Level 7 (33,972 points)

    One of my favorite pre-G3 Macs! I have one that runs great.


    ---First, has anyone pulled/replaced/moved RAM modules? My experiences with several 7600's at work back in the 1990s was that the RAM needed to be matched in order in the slots and by size regardless of what the specs and several third-party tech reviews say.


    There are eight RAM slots in two groups (of three and five slots) separated by an offset slot for a cache module You should see ID codes on the logic board by each slot: A1, A2, A3, A4; and B1, B2, B3, and B4. You want to load the slots in this order: A1, B1, A2, B2, etc, and match the module size so modules of the same size are paired. My 7600 has this pattern:


    A1: 128MB        B1: 128MB

    A2: 32MB          B2: 32MB

    A3: 16MB          B3: 16MB

    A4: 16MB          B3: 16MB


    So, if modules don't match, match them and try again


    Pairing RAM in this model gives a significant performance boost; the data path goes from 64-bit to 128-bit.


    ---Is the OS9 disk a full retail install disk or a gray one that came with a newer Mac? That could affect startup, Some disks for much newer Macs may not start a pre-G3 Mac.


    ---If the commuter has been off wall power for a long time the PRAM battery is likely deader than Yorick. That could affect startup from the hard drive but should not be at play when starting from a CD.


    ---Another issue  that affects old computers that have been stored and moved around is loose cards. Make sure all card and modules are fully seated, especially the processor card.


    Anyway, those are some things to consider. Keep us posted!

  • Jeff Level 6 (11,477 points)

    Have you tried to boot the computer from the optical drive, while simultaneously pressing/holding down these 4-keys: Command + Option + Shift + Delete?  You should probably buy/install a new 3.6-volt, ½AA lithium battery, because as Allan mentioned, it's likely dead.  Depending on where the computer was stored, humidity may have caused oxidization of the gold-plated contacts on the processor card and memory DIMMs.  I'd inspect the processor card first, and if the contacts appear discolored, use a (soft) white eraser to gently scrub them.  Be sure to blow off any rubber shavings left on them, before re-installing the card.  If the processor card's contacts are discolored, the memory DIMMs undoubtedly need to be cleaned also.

  • nOmada Level 2 (175 points)

    Regarding the RAM modules all are OWC's 128 MB so I'm guessing the pairing is not an issue.

    The battery is new I just replaced it. The Mac OS 9.1 CD is a backup and it works on a B&W G3

    and don't have a retail CD.


    Here's what I could do so far: I have a Retail Mac OS 7.6 CD (It's the only that works besides the original Mac OS 7.5.3 CD) that it could boot from and could format and install on a 150GB Hard drive via a PCI Sonnet Tempo Trio card. The bad thing about it it's that this system works on the old HFS system. So what I did next was to try to boot from a Mac OS 8.6 CD and it worked, then reformated to HFS Plus and installed Mac OS 8.6. After that I tried to boot from the Mac OS 9.1 CD and again it didn't work so I installed the Mac OS 9.1 but running the 8.6 system. Is this OK? Or is something affected by doing the installation this way?


    Thanks a lot.


    Some specs


    8 128 MB Modules of RAM for a total of 1 GB

    Sonnet PCI Tempo Trio 133

    ATI Radeon PCI 9200 video card 128 MB