RAM problems with a Pismo

Following great advice from you guys (jpl and Cornelius etc), and after my usual very long period of procrastination before getting a job done following ordering all the parts and then having them sitting around, I finally upgraded the HDDs of my two Pismos (a 400MHz and a 500MHz) to 60GB and 120GB respectively. All of that went very well using great IFIXIT instructions and SuperDuper!/Carbon Copy Cloner software - I tried them both to see how they worked and they were both very good. I then successfully installed Tiger into both of them after upgrading their RAM. Now the bad news, I had originally ordered four Low Profile 512MB RAM modules on eBay of the correct specification quite a while ago from the FastMemoryMan/Emartbuy outfit to upgrade both Pismos to the maximum of 1GB RAM each but I had not tried to install and use them until very recently. When I did, none of them worked and it was so long ago that I've now completely done my dough in regard to returns and warranty - all my own fault, unfortunately! Being a glutton for punishment, I ordered four more 512MB RAM chips on eBay of the correct specification for Pismo from the SmileNTango outfit. This time just TWO of them worked but the other two did not so I was able to max out the RAM in the 500MHz Pismo to IGB. I am now in negotiation with SmileNTango about returning the ones that did not work and they have offered the option of a full refund for them. However, they are also telling me that the reason they did not work was not because they were faulty but because the Pismo motherboard is 'picky' about RAM specs and their regular RAM modules are not guaranteed to work with it. However,for quite a bit of extra money (funny, that), they can supply me with two types of RAM that will work. The price differences are huge and I know I could get modules from OWC at a much better price. Does this explanation sound correct - I must say that it doesn't to me! How is it that I ended up with so many RAM modules that did not work in my Pismos and is it true that not all of these types of 512MB modules will work correctly in a Pismo. Can the modules be tested and/or repaired or are they now just junk? I did not expect this problem but, on a much more positive note, I was very pleasantly surprised at how easy it was to upgrade the Pismos and I really enjoyed doing the upgrades, after feeling quite daunted by it, and I would encourage anyone else to give it a try. I just love those Pismo Powerbooks. I am now going to upgrade my iMac after ordering all the upgrade parts - another job I have been putting off! Many thanks in advance for any advice or information. Cheers, Steve

iMac G4/800/256MB, Mac OS X (10.4.11), Pismo G3/500MHz/1GB & Pismo G3/400/192MB

Posted on Dec 9, 2008 6:39 AM

Reply
13 replies

Dec 9, 2008 6:29 PM in response to cornelius

Many thanks, Cornelius - I am now going for the refund option. I was under the impression that the RAM under the daughterboard had to be Low Profile but that it did not matter for the one on top - is this not correct? Also, is non-Low Profile cheaper than Low Profile? I now take take your point about not buying RAM on eBay - it's a minefield! However, after a brief on-line survey, the prices for these RAM modules in Australia were quite high - two or three hundred dollars each - almost more than the Pismo is worth! Even on ramseeker they are not particularly cheap and there also seems to be quite wide variability in pricing. Should I get a refund for all four of them or do I keep the two that work - ie will they keep working? I was inclined to keep the ones that work because they were not very expensive - much less than most of the prices in ramseeker. I noticed OWC was doing these 512MB modules for around $30.00 - would these be 100% reliable? Otherwise, I was thinking of the Memory Systems ones at around US$55 - would these be reliable? Thanks, again. Cheers, Steve

Dec 9, 2008 7:00 PM in response to Steven Pyott

Steve:
I was under the impression that the RAM under the daughterboard had to be Low Profile but that it did not matter for the one on top - is this not correct?

That is true for the WallStreet. The Pismo will take standard RAM modules.
Should I get a refund for all four of them or do I keep the two that work - ie will they keep working?

I would keep the ones that work. If they are sound, they should continue to work. You can test RAM by running the Apple Hardware Test from the disk which came with the computer, or you can use Rember-Memory Test.
I noticed OWC was doing these 512MB modules for around $30.00 - would these be 100% reliable?

Yes. OWC is an excellent source. Their products are reliable as is their customer service and tech support. I would have no hesitation buying from them.
the prices for these RAM modules in Australia were quite high - two or three hundred dollars each - almost more than the Pismo is worth!

I was not aware that you were in Australia. Sorry 😟 (not sorry that you are in Australia, but because I was not aware of it). You might want to include your location in your profile. It is helpful to us as we attempt to answer your questions.

😉 cornelius

Dec 15, 2008 10:27 PM in response to Steven Pyott

Hi Cornelius, Just to round this item off. I am still going through the refund process with SmileNtango but it is looking OK so far. However, I ordered the two 512MB RAM modules from OWC and they arrived lightning fast in what seemed like three days all the way from the U.S. to Australia. I put them in the Powerbook and they worked perfectly first time. I should obviously have gone there first. So both Powerbooks are now fully upgraded and working perfectly using 10.4.11. Many thanks for all the help. Now to upgrade the iMac/800/256MB with a new 500GB HDD, a new Superdrive and 1GB RAM! Cheers, Steve

Message was edited by: Steven Pyott

Dec 16, 2008 12:04 AM in response to Steven Pyott

Hi, I'm sorry to drag this out some more and I know this will sound like I am just engaging in wishful thinking but browsing through iMac/G4 upgrade discussions for encouragement, I noticed one posting that suggested that if the Mac doesn't recognise newly installed RAM modules, then the PRAM and NVRAM should be re-set, as per Apple instructions HT1379. Indeed, it stated that these should always be re-set when changing the RAM profile of a Mac computer. I didn't do this with any of the RAM modules that worked straightaway after installation but I never tried it with any of my non-working RAM modules. Is it possible that this would make the previously non-functioning RAM modules be recognised by the Powerbooks? Of the batch of four identical modules I ordered most recently, two worked straightaway but two didn't and I was wondering whether this procedure could make these two work. I wanted to ask here before I tried it myself in case it was a risky procedure with unreliable RAM. Cheers, Steve

Dec 16, 2008 7:01 AM in response to Steven Pyott

Steven:

NVRAM is the Intel Mac equivalent of what we know as PRAM in PowerPC Macs. The PRAM stores certain parameters of the computer (See Mac OS X: What's stored in PRAM) and resetting clears the memory stored in the PRAM. PowerBook G3 has a PRAM battery that supports the storage of this information. However, to the best of my knowledge, resetting the PRAM does nothing to make non-operative RAM modules operative. And, of course, since only Intel based Macs have NVRAM resetting it does not apply to your Pismo.

😉 cornelius

Dec 16, 2008 10:13 AM in response to Steven Pyott

Steven,

Your powerbook does has NVRAM and PRAM, both retaining settings when the computer is powered off. It is always a good idea to reset the PRAM and NVRAM when changing memory modules, but I would speculate that most of us do not. I can't answer whether your other modules will work after a reset. However, you can test one module at a time in the top slot so you don't have to pull the microprocessor card; then just check your System Profiler for memory stats.

http://support.apple.com/kb/HT1379?viewlocale=en_US

Dec 16, 2008 12:17 PM in response to jpl

jpl:

Thanks for correcting my information, but I'm still confused. My response was based on the article When to reset NVRAM or PRAM which says:
On Intel-based Macs, this memory known as NVRAM; on PowerPC-based Macs, this is known as PRAM.

As I do not wish to continue to perpetuate misinformation, can you help me understand the contradictions. My understanding is that NVRAM is Non-volatile random access memory and is used to refer to RAM which does not lose information when the computer is turned off, somewhat like Flash memory. Again, my understanding is that with our G3 PowerBooks that the parameters are kept in memory by the PRAM battery power so that the RAM itself is not non volatile.

This is a new area of inquiry for me, so any assistance you can give me to understand it better will be helpful.

😉 cornelius

Dec 17, 2008 9:03 AM in response to Steven Pyott

Steve:
sorry to be the cause of an unanticipated Pismo mystery.

Not at all. Indeed, part of the benefit of posting in Apple Discussions is that I am able to learn about Macs in general and my Pismo, in particular. I have learned a great deal from jpl and have the greatest respect for him. I hope to continue to pick his brains to learn more of what he knows.

Sorry resetting the PRAM or NVRAM or whatever one resets on a Pismo, did nothing for you, but then neither you nor we expected much. At least that mystery has been resolved.

Cheers 😉

cornelius

Dec 17, 2008 10:16 AM in response to cornelius

Cornelius,

I really cannot answer your question competently. As I understand the basics, a small part of RAM is segregated and used for PRAM settings and is maintained by the PRAM battery when the computer is powered off. In the case of powerbooks, these settings can also be maintained when the computer is turned off by a charged main battery and/or power adapter.

I have also read that there is a separate NVRAM chip that stores other settings, most likely related to power management, and the settings in this chip are also maintained by the PRAM battery.

When you reset the power manager and PRAM, you remove the power maintaining them. As the computer starts up, a new instruction set from ROM chips is loaded in the NVRAM and PRAM.

Since I may be incorrect on the above, you might post a query in the Lounge.

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RAM problems with a Pismo

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