[Darren K]

I wasn't able to find anything on the subject, and in preparation for an upcoming Mac Pro purchase, which I plan to have 6 or 8 GB of RAM, I am wondering why there is a substantial price difference between 1 and 2 GB RAM modules when an equal sum is reached. Is there a performance gain to be had using 2 GB modules, or is it simply that they are more expensive to manufacture?

Thanks.

[subego]

The only performance gain is that you use one slot, leaving the other slot open for more RAM.

More RAM will equate to better performance.

I'm going to guess the Pro has 4 slots.

This would make 6GB: 2 2GB chips and 2 1GB chips.

This would be cheaper than 3 2GB chips (which wouldn't work because you have to use an even number of chips) and way cheaper than 4 2GB chips, which is how you get 8GB.

Does that make sense?



Edit: though I'd need to ask you a few more questions to be sure, the fact you are even considering 8GB means you probably need 8GB.

[mduell]

The number of chips on the memory modules (unless you're buying really small capacity ones) is fixed. The only way to double the capacity is to double the density, which drives the price up (more expensive to manufacture, less manufacturers making them, etc).

Performance has a couple metrics (bandwidth, latency) and is mostly determined by the number of modules installed rather than their capacity. 4x1GB is faster (in bandwidth; same latency) than 2x2GB, but 4x2GB is faster (in latency; same bandwidth) than 8x1GB.

[Darren K]

mduell, that answered the question perfectly. Thanks.

Originally Posted by subego

the fact you are even considering 8GB means you probably need 8GB.

I don't need a new computer, either, and could probably keep chugging away on my G4, 450.