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  • Priest of the Order of the Butterfly
    Priest of the Order of the Butterfly
    MarK
    Posts: 641 from 2004/1/25
    From: Prague, The Cz...
    Hi all,

    just a question, is there still a problem of using more, than 1.5 gigs ram? afaik, this was problem with Pegasos and OF, but why this limitation remains with PowerMac/PowerBooks? What's the problem of having more memory?

    Thanks in advance,
    Martin.
  • »24.04.13 - 10:24
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  • Paladin of the Pegasos
    Paladin of the Pegasos
    Amigaharry2
    Posts: 1282 from 2010/1/6
    From: EU-Austria (Wien)
    AFAIK is the problem not the Pegasos but MOS itself.....
    Peg2, 3xPowerMac G5, 2xPowerbookG4, 2x MacMiniG4, Efika (again), A3000T and life is never boring.....
  • »24.04.13 - 11:33
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  • Yokemate of Keyboards
    Yokemate of Keyboards
    Andreas_Wolf
    Posts: 12163 from 2003/5/22
    From: Germany
    > is there still a problem of using more, than 1.5 gigs ram?

    Yes, there is. You can put in more than that of course, but MorphOS won't be able to use more.

    > afaik, this was problem with Pegasos and OF

    No, Amigaharry2 is correct. The barrier with most Pegasos II board revisions is at 1 GiB, which is a hardware/firmware limitation and thus has nothing to do with MorphOS or any other OS.

    > why this limitation remains with PowerMac/PowerBooks?

    Because it's basically still the same MorphOS.

    > What's the problem of having more memory?

    In a nutshell:
    - not more than 4 GiB due to lack of 64-bit addressing
    - not more than 2 GiB due to 31-bit barrier for OS3 API compatibility
    - not more than 1.5 GiB due to reserved PCI address space etc.

    More there:
    https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=6634&forum=3&start=7
    https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=5724&forum=11&start=22
    https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=8756&forum=3&start=1
    https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=8980&forum=3&start=5
  • »24.04.13 - 12:08
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  • Priest of the Order of the Butterfly
    Priest of the Order of the Butterfly
    MarK
    Posts: 641 from 2004/1/25
    From: Prague, The Cz...
    thanks for the explanation (again), but then I can see, that could be a possibility to get more ram (if i have 2 gigs installed), if I drop some of unused pci address space... a simple tool like addmem (of old days) could do that, would that be possible? say, 1.8 gigs would be possible?

    Martin.
  • »24.04.13 - 12:20
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  • Paladin of the Pegasos
    Paladin of the Pegasos
    SoundSquare
    Posts: 1213 from 2004/12/1
    From: Paris, France
    [quote
    No, Amigaharry2 is correct. The barrier with most Pegasos II board revisions is at 1 GiB, which is a hardware/firmware limitation and thus has nothing to do with MorphOS or any other OS.


    Are you sure about that ? I'm sure i was using 2gb on my peg2 back in the days with Gentoo linux, one option had to be enabled in the kernel in order to have the full use of the 2gb
  • »24.04.13 - 16:56
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    • Yokemate of Keyboards
      Yokemate of Keyboards
      Zylesea
      Posts: 2057 from 2003/6/4
      MarK,
      Quote:

      say, 1.8 gigs would be possible?


      AFAIK 1.8 gigs is the maximum on OS4, hence I guess that amount should be possible with MorphOS, too (if OS4 doesn't do any dirrrrty tricks that is).
      --
      http://via.bckrs.de

      Whenever you're sad just remember the world is 4.543 billion years old and you somehow managed to exist at the same time as David Bowie.
      ...and Matthias , my friend - RIP
    • »24.04.13 - 19:14
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    • Yokemate of Keyboards
      Yokemate of Keyboards
      Andreas_Wolf
      Posts: 12163 from 2003/5/22
      From: Germany
      >> The barrier with most Pegasos II board revisions is at 1 GiB, which is
      >> a hardware/firmware limitation

      > Are you sure about that ?

      Yes, I am.

      > I'm sure i was using 2gb on my peg2 back in the days with Gentoo linux

      A year ago you told here on MorphZone that you suddenly had crashes when compiling after you had switched from 1 GiB to 2 GiB:

      https://morph.zone/modules/newbb_plus/viewtopic.php?forum=11&topic_id=5724&start=62
    • »24.04.13 - 20:11
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    • Paladin of the Pegasos
      Paladin of the Pegasos
      SoundSquare
      Posts: 1213 from 2004/12/1
      From: Paris, France
      Quote:

      A year ago you told here on MorphZone that you suddenly had crashes when compiling after you had switched from 1 GiB to 2 GiB:



      that's correct, compiling was causing crashes, but desktop use was fine, i never got sure if it was a hardware limitation from the pegasos or faulty (or badly supported) memory modules. I also don't have your impressive memory : )
    • »25.04.13 - 15:07
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    • Yokemate of Keyboards
      Yokemate of Keyboards
      Andreas_Wolf
      Posts: 12163 from 2003/5/22
      From: Germany
      > compiling was causing crashes

      That's a way how the mentioned barrier makes itself felt. The heavier the memory use (and compiling is very heavy), the more error-prone and unreliable it becomes.

      > desktop use was fine

      Maybe you didn't notice the corrupted bits/bytes, which would be a case of illusive data integrity. Or maybe your desktop use is just not very demanding for the memory ;-)

      > i never got sure if it was a hardware limitation from the pegasos
      > or faulty (or badly supported) memory modules.

      If your board was a revision 2B5 one then the latter would have been the cause. With a lower revision the barrier is a fact, as has been explained by geit in the old thread.

      > I also don't have your impressive memory : )

      At times it is corrupted too ;-)
    • »25.04.13 - 16:19
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