How to test 'Matching' memory modules - iMac G5 (ALS)

Question

Hi there,
Does anyone know of a way of checking whether memory modules are working at 128-bit rather than 64-bit?
For reasons of cost and availability, I have installed two 1GB DIMMs from different manufacturers in my iMac G5 (ALS).
As per the Apple article:
http://docs.info.apple.com/article.html?artnum=300082
The specifications seem to be matching ie, they are both:
184-pin
Non-EEC
Unbuffered
PC3200U-30330
CL3
16 devices
So, in theory, they should be working at 128-bit in dual-inline mode. System Profiler just says they are both 1GB PC3200U-30330 modules and that they are both OK.
So is there a way of telling for definite...out of interest...my computer seems a bit nippier but that could just be the increase in RAM from 1.5GB to 2GB.
??

Answer 1

So, when ordering RAM, what's the trick to ensure you get matched 128-bit
capability? I missed the "gotta have stats".
From my experience, the biggest issues are:
1) same number of components (same chip count front and back)
2) same CAS latency
for example, in the numbers: PC3200U-30330
the first "3" in 30330 is the CAS latency. The other numbers after that can be different, but you want the CAS latency to be the same. I don't know what the other numbers mean.
PC3200 is just the type. Most likely you have the same type. Otherwise, you'd have other problems.
I've purchased, mixed and matched, and installed several different modules, and as long as they were the same CAS latency and chip count, they registered as "matched".
You can check the numbers for your modules by going into system Profiler, and clicking on the "Memory" in the list on the left.
System Profiler is in: Apple Menu --> About this Mac --> More info.
Hope this helps.