Upgrade memory ram Powerbook G4

Hello and welcome to the support community

This looks to be the correct memory according to this link,

http://www.everymac.com/systems/apple/powerbook_g4/specs/powerbook_g4_1.25_15.ht ml

Hope this helps

Hello,

Your PowerBook should be fine running on 2 x 1GB PC2700 unbuffered memory.

I have the same PowerBook which has a 2GB DDR PC2700 bus speed of 333 MHz running successfully.

I've not know it to have any performance problems :) stick to the above and you should be fine.

Hello,

Sorry to read you are having difficulty with the new RAM you ordered.

You received the incorrect RAM from the supplier, then you have the right to return them and be sent the correct Samsung memory you ordered.

What type of memory did they send you?

When you say reset the PowerBook, why do you need to reset it?. If you put your old memory back in, surly everything should work as it did before.

Do you mean reinstall Mac OS X?

I wish I'd noticed your post earier. You PowerBook is one of four PowerBook G4 variants that uses a technology called bus slewing to give a longer runtime when on battery. The system bus clocks back, effectively reducing the overall speed, when you run on battery power. I don't know what it is for the 1.25 Ghz but my PB G$ 17-in 1ghz clcoks back to an equivalent of about a 667mHz compuer.

Apparently RAM must support this technology. Here is the RAM description from one of my two trusted RAM vendors for your model:

http://www.datamemorysystems.com/_apple_info/Apple_G4_PowerBook_1.25GHz_15_Memor y_1211.asp

Note the mention of bus slewing:

NOTE: This is one of four Bus Slewing PowerBooks that Apple released and it has very specific memory requirements. The memory modules listed below are specific to this PowerBook. Not just any memory will work in this PowerBook

Hello Allan,

This is very interesting. The details I have about Bus Slewing (as it's been said) appears to only effect the A1095 (1.5Ghz model) according to my old Apple paper work (dated Oct 2004) So I find it interesting how such was applied to the 1.25 Mhz model as well.

Thanks for the information 🙂

From the rest of the DMS website, they list the following PBG4 models as using bus slewing:

• 17-inch 1gHz
• 15-inch 1gHz
• 15-inch 1.25gHz

I can't find the fourth they claim in their list of models.

Then there is this CNET artice from way back:

http://reviews.cnet.com/8301-13727_7-10343213-263.html

It has this chart:

• PowerBook Processor Buses
• 15" 1.00 GHz 612 MHz - 1.00 GHz 102 - 167 MHz
• 15" 1.25 GHz 765 MHz - 1.25 GHz 102 - 167 MHz
• 17" 1.33 GHz 815 MHz - 1.33 GHz 102 - 167 MHz

From the article is sounds like the advantage of slewing over the tradional "A/C v. battery" preferences setting is that, although clocked back when on battery, a slewing model CAN speed up without the user switching anything if the works demands full power from the system.

Out of date now but still fun stuff!

Thank you Alllan.

I wonder if this technology is currently being used in the MacBook range. Assuming that the development was successful in the PowerBooks and G5 as stated in the article. I knew such existed, but not made public by Apple when selling the PowerBook G4 in 2004/2006

Was two types of memory actual made, one that supports this technology and one that doesn't?

Surly it's a case of the machine governs the drop or increase is bus speed regardless of the memory. Therefore allowing the correct standard type of memory to be used. I wonder why this was not applied to the 17" 1.67Mhz with high res screen? Considering the advancements that made to the last model before the MacBook Pro range came out.

Interesting stuff 🙂

Morning Knuckles.

I wonder if this technology is currently being used in the MacBook range.

Not exactly. MBPs and MBs clock back the processor speed if you run on wall power with no battery installed: MacBook and MacBook Pro: Mac reduces processor speed when battery is removed while operating from an A/C adaptor

There is no official amount listed but, back in the days when my Late 2007 MBP was "sierra hotel" as my USAF friend says, some knowledgeable tech people around here were saying the clockback was to 1Ghz or 1/2 of full processor speed, whichever was greater/

Was two types of memory actual made, one that supports this technology and one that doesn't?

For aftermarket, apparently yes. There was a big whizzing contest back then because Crucial had a "one size fits all" approach to PB RAM and the smaller vendors and some PowerBook service specialists were screaming about Crucial not supporting bus slewing and, due to the size of their customer base, messing up a lot of PowerBooks.

Currently, DMS specifically mentions the need for special RAM for certain models. Whether all their PowerBook RAM supports slewing, only they know, but that would be an effective way to handle inventory costs--sell slewing RAM for all PowerBooks.

OWC does not specify, but were deep in the RAM conflict on the side of supporting bus slewing. I've never seen a post here where OWC RAM failed as long as the customer ordered the right stuff.

Therefore allowing the correct standard type of memory to be used. I wonder why this was not applied to the 17" 1.67Mhz with high res screen?

Could be people didn't like the computer deciding when to slow down and speed up. The later system of providing a pref pane puts the user in the pilot's seat. We can't know for sure, but I am sure, like you, that this is interesting stuff!

AJ