At 12:58 -0700 09/21/2002, Bolton Peck wrote: >Upon bootup from cold I am getting a 'type 11' bomb error on my J700, it >happens regularly at the end of the icon parade which is my extension >loading :-) If I power down, take the lid off, unseat and reseat the >CPU card and push down on the PCI cards, then reboot it will usually >come back up. However running mem test software results in no indicated >RAM problems. Although Gauge pro only tests the RAM that's free, in my >case the remaining 90MB or so of 160 which is free when runningthe >machine. > >So my question is, how is the memory mapped in Mac OS and within the >machine? That is, does the Mac OS get put in the lowest available >address, and does that correspond to motherboard RAM?
I don't know whether the motherboard RAM is at the high addresses or the low. However, it appears that the Mac OS mostly loads starting at the lower addresses, but there's also some stuff that seems to go at the highest addresses. So it's not as simple as we would like it to be. Another nice list member sent me a memory utility several months ago that made this apparent. Of course, my leaky wetware memory doesn't remember the name of the kind list member nor the name of the utility. > I would not be >averse to unsoldering the slower 70ns mobo RAM chips, since I have >plenty of other RAM in the box. Do I have to unsolder all of the pins >or could I just disconnect the power pins? I don't think that you can just unsolder the power pins. The memory is in an SOJ package which means it has pins like a PLCC chip. They are thick and bend under the chip and curl. You'd be hard pressed to desolder them and bend them out of contact with the underlying pad. You'd pretty much need to desolder the whole chip. Technically, just desoldering the power pins might do the trick of disabling the motherboard RAM. I'm just saying that I think it's physically impossible to very difficult to do so. BTW, the RAM chips in our machines (or at least the one I examined) are 1M X 16. Which is a little odd, because eight chips of that sort gives a width of 128 bits unless they divided it into two banks or something. The memory bus is 64 bits wide. Or, if it is interleaved it makes sense. Kennedy? Didn't you write a few years back that the motherboard RAM *is* interleaved. I've been hunting around for a 8M X 16 or 4M X 16 in a 42 pin SOJ which would take the MB RAM to 128 MB or 64 MB respectively. Doesn't make much economic sense, but if one wants to get the S900/J700 over 1 GB this would do it... Anyway, if ultimately you do need to desolder the memory chips, and if you need advice, Mad Dog or I can probably give you pretty easy to follow instructions. They'll involve buying Chip Quik though... But I think this is unlikely. >The above is based on the assumption that a type 11 error relates to >memory, and that it could be hardware related since pushing and prodding >the motherboard seems to temporarily cure it. I'm not sure about this. The first thing I would try is booting with extensions disabled. If the problem goes away, try hunting for a single extension that is causing the problem. I might also try booting from a different volume or CDROM. In other words, check to make sure that your problem is not caused by a conflict or corrupt software before modifying your hardware. The fact that the problem goes away after you reseat the cards seems to indicate hardware, but I've seen a number of problems that seemed to be hardware that turned out to be coincidences. In my experience, freezing right after the extension march is more often a corrupt OS or extension conflict than a hardware problem. Another possibility is that your CPU may be overheating and that's how long it takes to overheat. Do you have it overclocked? >Finally I should note that I soldered in one more PCI slot, and it works >fine with firewire card installed into it. I desoldered the other slot, >but then accidentally damaged the other PCI socket I had on hand to go >in there, so the board is ready for the other PCI slot to be installed, >that is, the pin holes are open. Could the open pin holes in PCI slot F >cause this problem? I don't think that the work you did on the PCI slots would cause this problem. These systems are so complex that almost anything is possible in wierd cases. :-) But based on past experience I don't think this is related to your PCI slots. The easy check here would be to remove the cards in the lower slots and operate just top slots for a while. The problem with this test is that removing the lower cards would probably cause some extensions not to load, and those extensions might be the root of the problem, rather than the physical PCI cards or slots. Yet another complicating factor is that if you do indeed have a memory problem, it could be just the last extension or two to load, regardless of which extensions those are, that causes the problem. That is, it may take X number of extensions to fill the memory up to the problem spot. This is also unlikely, but a factor to consider when you are designing your troubleshooting approach. Still, I think the place to start is a common boot with extensions off and then extension hunt if indicated. Plus boot from another volume or a CDROM and see what data you collect. >Finally, would it help to reinstall OS 8.6? (I don't have anything newer >or I'd be using it..) To the extent that you may have a corrupt OS component or extension conflict this may help. Jeff Walther P.S. I'm probably going to be doing a Digi-Key order in the next couple of weeks, so if you'd like me to order you a PCI slot I could. You'd need to pay the postage from me to you (probably about $1 with the cost of the padded mailer included) but that should still be cheaper than ordering it yourself if that's all you need from Digi-Key. -- SuperMacs is sponsored by <http://lowendmac.com/> and... Small Dog Electronics http://www.smalldog.com | Refurbished Drives | Service & Replacement Parts [EMAIL PROTECTED] | & CDRWs on Sale! | Support Low End Mac <http://lowendmac.com/lists/support.html> SuperMacs list info: <http://lowendmac.com/supermacs/list.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive: <http://www.mail-archive.com/supermacs%40mail.maclaunch.com/> Using a Mac? 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