What I would like to see someone write is "that isn't your fault".
Last night, immediately after installing a 1 Gig upgrade kit from Ramjet in my SP G5 1.8, my factory original 512 MB RAM was no longer being recognized. "About this Mac" only reported 1 Gig of RAM, although it should have reported 1.5. I booted hardware test DVD, and although it sees the two 256 MB RAM DIMMs, one of them is getting a "post/0/2048" error on startup.
I tried moving the RAM (original and upgrade) into different slots, and running each by itself. The Ramjet DIMMs run fine, but I can't even get the machine to boot with only the original Apple supplied RAM.
I want to think that the original RAM has gone bad, and that it's just an amazingly suspicious coincidence that the problem didn't show itself until after installing the upgrade. Prior to the upgrade, I had no real problems - even Doom 3 ran reasonably well, once I turned off some of the eye candy ;-)
I suspect that somehow, in some way, I fried the original Apple supplied Samsung RAM. And, I suspect that when I call AppleCare later today that's what they'll tell me, and refuse to fix the problem.
Any thoughts?