I have a g5 iMac rev A with stock memory (256MB) and I'm looking to make an upgrade. I plan on going through Crucial, but I've encountered the whole "ram matching" issue as I've done a little research. So my question is: is it worth matching the 256MB stick in the G5 to upgrade to 512 MB with a 128-bit bus or should I just get the 1GB stick and move up to the 1.25 GB range of memory and leave the bus at 64-bit?? I'm new to this stuff so pardon me if this is a dumb question. Thanks.