Apple PowerBook G3 FireWire Pismo 400 Mhz/1GB/120GB???

a brody:

I can appreciate the problems that poor quality RAM modules can cause. My question was specific to the topic under discussion here. That is, assuming that we have high quality RAM and a tested sound module, how do that factors play out in terms of the Pismo, for example, which easily runs PC 133 RAM, albeit at the spec speed of PC 100? To the best of your knowledge, is this the case with any other Mac laptops? In terms of the difference between the Apple specs for Maximum RAM supported and the actual, the rationale offered by both jpl and Hardy seem reasonable to me, or is there something that they, and I, missed?

cornelius

assuming that we have high quality RAM and a tested sound module,

This is a pretty big assumption to make. I don't care who the RAM manufacturer is, they can't thoroughly test the RAM module in the age of the universe. Do you wish to be the one who is unlucky today? With 1 billion circuits, and 1 billion factorial combination of circuits, there is no way even with the highest quality RAM to ensure the RAM is going to work 100% of the time. Why introduce another unknown variable to the equation of bad RAM by adding RAM that is not officially to spec? At least if you are to spec, you stand better chance than if you don't. It still may be imperfect, it still may kernel panic, but it won't be because it isn't to spec. Eliminate the potential for error as much as possible. Why introduce extra elements of risk? Do you want a jalopy that has many mismatched parts, or do you want as closely configured to normal as possible?

a brody:

I have difficulty following your rationale. If it is impossible to adquately test RAM, and if the millions of modules out there are accidents waiting to happen, and one minimizes risk by sticking with specs, then there should be computers crashing all around us all the time. I have RAM which are not strictly specs, and they are cheap RAM, too! Yet I have never had a KP related to RAM. Yet there are lots of folk we see in these forums who have RAM that meet specs, whose computers KP from time to time. Russian roulette? That seems to defy the law of chance.

cornelius

You are only one computer whose machine isn't to spec. You are witnessing thousands on Apple Discussions who kernel panic, get spinning beachballs, overheat both to spec, and not to spec. Don't forget kernel panics aren't only due to bad RAM, but also bad directories, and drivers not tested with the operating system in question.

I don't think it defies the odds of chance to have a few computers not to spec that don't kernel panic, whereas a few thousands that are to spec that do. Many more have something else that aren't to spec either. You have no idea what else many of these people have added. I've seen way too many that once you delve into what they've done, that you realize there is something not to spec, where on the surface it looks like there is not.

a brody:

You are only one computer whose machine isn't to spec.

There are lots of other Pismos with similar RAM configurations to mine. However, I think we are talking past each other, and in respect for the OP's wishes, I don't see much point in pursuing the discussion.

Thanks for your input. I appreciate your taking the time.

cornelius

needsomeihelp:

I am glad that your question was answered to your satisfaction. However, please be aware that this is a discussions forum, and that so long as the discussion is on point, I am not aware of any limits, even though the OP has marked the question as being "answered". Further, the discussion is open to any who wish to participate within the Terms of Use Agreement.

Good luck.

128GB is the upper limit for OSX, but not for OS9. For OSX the boot rom must be used but in OS9 the boot rom is needed to load the disk driver from the disk. Which is why the wallstreet's 8GB boot rom limit does not affect OS9. There are available drivers which can handle more than 128GB.

Hardy,

Yes, OSX is limited to 128GB and that is what the OP is running. But please note that I also addressed the OS9 limit when I quoted 200GB as the max. I should have included another quote from the article:

"If you plan to start the partition up from Mac OS 9.2.2, the partition sizes may be a maximum of 200 GB."

You say it is only upgradeable to 512MB but Apple's developer literature says:
An SO-DIMM using currently-available parts can contain either 32, 64, 128, 256,
or 512 MB of memory. *The computer can support up to 1 GB total RAM using*
*the highest-density devices available*, but SO-DIMMs made with such devices
may draw too much current in sleep mode to allow battery sleep swapping. See
“RAM SO-DIMM Electrical Limits”

So what Apple says that if you do the 1GB upgrade you may not be able swap batteries when the Pismo sleeping, I would not try such swaps with any amount of ram since the backup batteries on most Pismos are old and tired.

That's definitely an important point. I hadn't seen that article, and few vendors who sell RAM for it warn of that limitation. Many might find themselves in for a surprise. Do you have a link to that article?

I suspect that later memory chips require less sleep power, but memory makers are not always careful to include caveats.
The source is:
http://developer.apple.com/documentation/Hardware/DeveloperNotes/MacintoshCPUs-G3/PowerBook/PowerBook.pdf
There are similar technotes for all of the older Macs. The format has changed recently.

Thank you.