Sawtooth RAM Question

[Temetka]

So I've got my 450MHz AGP Sawtooth running.

However it is only recognizing 1GB of RAM.

According to LEM and everymac.com it will accept 2GB.

I have a 512MB and 3 256MB cards installed which should equal 1.25GB of RAM. No amount of moving modules / replacing chips gets it to recognize over 1GB of RAM. I have tried every slot, and every slot reads the RAM. However with all 4 slots filled, it will report 1 as empty and the other 3 as filled with the right size and speed being reported.

All RAM modules are PC133 and again, they all work but not all are recognized.

So I'm thinking either it's because I am using PC133 and not PC100 even though 133 will downclock just fine. Or it's a firmware issue. I have booted into Open Firmware and reset it a few times, pressed CUDA and even done the 3 fingered PRAM reset 3 times in a row.

Ideas, solutions?

The OS is 10.4.11

I have a 16MB Rage 128Pro AGP card and a Sonnet ATA/100 card installed. This is going to host files, be a backup for the iBook if I can get it running right. Thanks in advance.

 

[LCGuy]

Could it be an issue with the CAS latency of the RAM? I know some Macs from that generation are rather fussy, and prefer 2-2-2 RAM.

 

[tmtomh]

Apologies ahead of time for my ignorance on the details of which models are affected by what I'm about to say, but...

... isn't there some issue with some PPC Macs not liking the "high density RAM" that some Intel PCs can use? Might some of your RAM be high-density?

 

[Mike Richardson]

Compatible 512 MB modules must have a total of 16 chips, 8 on each side.

 

[Hrududu]

Is there one stick that is constantly not being recognized? Could just be a bad stick.

 

[phreakout]

If you have a copy of Tech Tool Pro 4 or the Apple Hardware Test disk that came with that Sawtooth, you can run that after installing the RAM to determine if any sticks are bad. You may have to run multiple tests overnight to verify everything is okay.

73s de Phreakout. b-)

 

[Temetka]

The memory all tests just fine.

We have 4 slots, 1,2,3,4.

I can have any stick in any slot and not matter what stick is in what slot, it tops at 1GB.

With only 3 lots being recognized as filled.

Ex:

512 slot 1

256 slot 2

256 slot 3

256 slot 4

would tell me 1GB available, slot 2 not in use.

Leaving the stick in slot 2 alone I move like this:

256 slot 1

256 slot 2

512 slot 3

256 slot 4

now slot 1 is not recognized. Still 1GB available.

So all the ram works in all the slots however I cannot get all 4 slots to activate at the same time and the deactivated slot is random.

I might try 4x256 and see if all 4 slots are recognized, but I want to be able to have at least 1.5GB or 2GB (max in OS X, in OS 9 it is 1.5GB) to help with minimizing disk swapping and to help the somewhat slow-ish 450MHz G4 out.

 

[Outlander]

A little late but....

You are using low density memory only right? The cheaper high density modules won't work.

 

[Temetka]

Yes all low density RAM modules here.

 

[ChristTrekker]

I've got a GigE/Mystic dual G4 now (thanks, coius!) and stuck in a couple 256MiB PC133 sticks I had. I run NetBSD on this machine, and while it sees these, it doesn't use them. The main difference, AFAICT from the dmesg, is that the working stick is double banked while these sticks are single banked. I used to have those sticks in a beige G3, and they worked just fine there.

Just another possibility for your consideration.