MP RAM: 2x2GB or 4x1GB?

[CanadaRAM]

4x1. If a stick fails, its no big deal...even running in pairs, you can pull one out and operate with 2x1 until the warranty item returns.
If you have 2x2 and one fails, you might have a problem.

Yup, and your chance of failure after it is in and tested, is somewhere like 0.25% per year. Not sufficient reason to spend more money, or to use your sockets up, unless you absolutely, positively know you'll never want to upgrade beyond 12 Gb

 

[disconap]

Nup. By definition, you don't have mismatched RAM in your PowerMac G5, it would not run without matched pairs - which is what you have. The G5 doesn't know from 256 bit access so there is no advantage to installing a matched 4-some, so matching between the different pairs is meaningless.

Sorry, to clarify--slots 1 & 2 have matched 1gb sticks each, slots 3, 4, 5, 6 have 512mb each, and slots 7, 8 hat 256 each. Is there a more optimal arrangement?

 

[Multimedia]

Have you studied the chart?

I've searched google and this forum and can't find a definite answer:

MP: 3GHz Quad Core Xeon.
I'm trying to figure out if there is a big (noticable) difference in speed between upgrading RAM with less of a bigger size (2x2GB) or more of a smaller size (4x1GB). I realize that both the 2GB and 1GB chips are still 667 MHz, so my instinct tells me the 4x1GB setup will be able to handle a larger load (since it has 4 chips at 667 vs. 2 at 667). Does anyone know with greater certainty? Also, with the quad core processors, is there a benefit to having 4 separate chips?

You are fantasizing about sticks. There is no advantage to buying 1GB sticks. You should NEVER buy 1GB sticks any more. There is no advantage to using 1GB sticks.

Two 2GB sticks cost $205. You install your RAM according to this chart. End of story.