• Order of the Butterfly
    Order of the Butterfly
    sailor
    Posts: 398 from 2019/5/9
    From: Central Bohemi...
    Quote:

    Andreas_Wolf wrote:
    > With higher frequencies ( 1.4 GHz and above ) I had memory read errors.
    > From my opinion is northbridge MV64361 responsible for this, not CPU.

    The northbridge being responsible for this doesn't seem plausible to me. The northbridge does not care for the CPU clock rate at all. It runs at the same clock rate no matter the CPU clock rate.

    > the max frequency is 1.464 GHz

    Is it a given that 11x is the highest possible multiplier? After all, the 5 binary digits of the PLL config can theoretically represent 32 different numbers, and with 0.5 steps this could amount to a 2.07 GHz range.


    maybe, I don't know and have no way how to test it. Higher frequencies then 1.333 makes memory error.
    Of course, It can be done on processor side. But also some synchro issues on northbridge.

    yes, in theory 5 pin = 32 possibilites.
    But if I see the table obr-3.jpg I have no idea how exact set higher frequencies.
    And for sure, I will try such things only with spare Pegasos or at least spare CPU card.
    AmigaOS3: Amiga 1200
    AmigaOS4: Micro A1-C, AmigaOne XE, Pegasos II, Sam440ep, Sam440ep-flex, Sam460LE, AmigaOneX1000
    MorphOS: Efika 5200b, Pegasos I, Sam460LE, Pegasos II, Powerbook G4, Mac Mini, iMac G5, Powermac G5 Quad
  • »31.05.19 - 14:54
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