Overclocking Question

in Current Mac Hardware edited January 2014
I overclocked my G4/533 to 600 MHz and after doing so ran [email protected] for a couple of days and it never had any problems with locking up after all that time. But twice now, once while installing Quicktime 6 and again while using internet explorer I have had Kernel Panics. Any ideas? I can't believe that a processor intensive app like Seti wouldn't show up and problems with heat.




  • Reply 1 of 7
    bartobarto Posts: 2,246member
    CPUs can deteriorate over time, but I can't imagine 533 @ 600 would deteriorate unless you upped the voltage.

  • Reply 2 of 7
    keithkeith Posts: 7member
    I didn't change the voltage.

  • Reply 3 of 7
    splinemodelsplinemodel Posts: 7,311member
    Quicktime may look for your graphics card or something, and you may have inadvertently modified the PCI bus speed, along with the system bus speed. THis also brings certain parcels of RAM into question. There may be some RAM on the chip, like an L2 or something, that chokes at the higher speed. Since L2s and the like are SRAM, they are entirely composed of transistors. If the transistors can't push a signal as fast as the clock, (that is, if the memory being pushed falls behind the clock) you get an error. In the EE world they call this a hazard.

    Try running at 566 and see what happens. I'm curious too.
  • Reply 4 of 7
    keithkeith Posts: 7member
    Well, I am not sure how to run at 566. The resistors I changed just alow you to go from 533 to 600 to 666 unless your change the bus speed which I left at 133. The utilities I have used say the bus speed is actually running at 137 MHz. I tried adding a fan last night on the CPU and so far I haven't had any more trouble except for IE crashing twice but it did that even before I was overclocked. Everything else seems to be working fine so far. I guess time will tell. Is it correct that the G4s like mine don't have a temp sensor in them anymore???


  • Reply 5 of 7
    splinemodelsplinemodel Posts: 7,311member
    not sure about the temp sensor, but --

    make sure your fan pushes or pulls air in the right direction. Make sure that it moves it the same way that the big, internal fan does. Otherwise you're actually doing more bad than good.

    Also, if you think heat is the issue, order some artic silver heatsink compound. It makes a world of difference: better than adding a fan alone.
  • Reply 6 of 7
    keithkeith Posts: 7member
    I did add some heat compound I bought at radio shack.

  • Reply 7 of 7
    splinemodelsplinemodel Posts: 7,311member
    [quote]Originally posted by Keith:

    <strong>I did add some heat compound I bought at radio shack.


    The Silicone stuff actually does a fairly decent job, though the Silver is better. I've never done side by side testing, so I don't know how much of a difference it makes, between silicone and silver.

    If you don't want to go back to 533, are still having problems, and are interested in a project, you could give water cooling a try, though it would certainly be a Project. (project with a capital P). Easier would be to furnish a bigger heatsink/fan combo. I don't recommend peltiers since they heat up the rest of your comp.

    Good luck. Just out of curiosity, have you tried using any programs to get the temp?

    [ 07-19-2002: Message edited by: Splinemodel ]</p>
Sign In or Register to comment.