[G4] Adding memory to a G4 PCI.

[Ronald Steinke]

On 30 April, 2006, at 3:31:12, Jono Carnie wrote:

> I've just added new memory to my G4 (PCI graphics) machine, two  
> sticks of 256mb pc133.
> The profiler shows it incorrectly as two sticks of 128mb.


A.   Did you test the memory sticks in another machine to verify that  
they are INDEED 256Mb apiece?

The reason I ask this is that one of our techs installed "256Mb" by  
using four 64Mb sticks and only found 192Mb when he rebooted the  
machine. It turned out that two sticks were really only 32Mb and had  
been put into the wrong box on the bench.

If another person can make this mistake, you could have also.

As for me, I personally test each stick on my desktop formatting  
machine before I install it in a customer box. I don't care if it  
came in a labeled wrapper or not. I have learned that people make  
mistakes and grab the wrong stuff more often than I like to think  
about and I don't want to be wasting my time and billing customers  
for any errors.

B.   Does the System Profiler list them in the corresponding slots on  
the motherboard?

I ask this because I have had RAM sticks that "looked like they were  
installed properly" but weren't all the way down in the slot and not  
connected at all. My Bad on that one. It could be "Your Bad" too.

On the issue of which RAM to use,

MacTracker says that your machine takes PC100, 3.3v, unbuffered, 8- 
byte, non-parity 168 pin SDRAM up to a maximum of 1024Mb. However, it  
has been my experience that using PC133 sticks instead will work as  
long as you do not have any other slower sticks installed. If you mix  
the speed types, the faster sticks will drop speed to match the  
slowest on board, so you would be wasting the effort of the upgrade.

The actual location (which slot?) hasn't seemed to make much  
difference so far in my usage, so I can't say that putting the sticks  
in right next to each other or separated is critical on that model.  
On some machines, it seems to speed operation a bit if the sticks are  
in the same numbered slot of each bank (ie: Bank A/Slot 1 and BankB/ 
Slot 1) as long as the sticks are the same size and speed (ie: 128Mb  
and 8ns each).

Just remember to not mix speeds when the specs call for matching  
speeds. A mix will cause a slow-down that most of us won't see with  
our eyes but which will show up during operations like image  
rendering. Of course, that only really applies if speed is crucial to  
your productivity or you are a serious gamer.