I just bought a new 2.4 GHz iMac (really nice computer), and I'm going to upgrade the RAM from 1 GB to either 2GB or 4GB. I'm going to buy the RAM from Crucial or OWC. I read the Intel Mac RAM guide on MR (http://guides.macrumors.com/Understanding_Intel_Mac_RAM), which was very helpful. Thanks to whoever put that together. I don't do a lot of intense work, but a few times a month I may create a DVD using iDVD. I know I'll benefit by having more RAM in that case, and RAM is really cheap right now so it's a very affordable luxury. My question is: will I see a big performance difference having 4GB vs. 2GB in iDVD encoding? I know more is better, but will all 4GB even be put to use? or will my processor max out to the point where there's plenty of RAM and not enough processor? How does that work? Edit: Also, does anyone know the CL of Apple RAM that comes pre-installed in new Macs? System Profiler doesn't tell me. "CL — CAS (column address strobe) latency, which is the number of clock cycles it takes before data starts to flow after a command is received. Lower CL is faster. Modules with different CL can be mixed on a system, but the system will only run at the highest (slowest) CL." Both Crucial and OWC sell this module as CL6. Is that pretty slow? BTW, for anyone considering an Intel iMac purchase, go for it. I love mine. It's really fast vs. my old iMac G5 and the screen is beautiful.