Thanks to those who replied to my RAM queries. I ended up trying 18004Memory and the 512MB dimm was $85. So i added the $14 to get it in 2 days via FedEx (since I saved some dough). Well, I'm sure you can tell what's coming. This is my lovely new 1 GHz TiBook that I just got a week ago, mind you. Everything has been working great--no problems whatsoever. So I run out to pick up my FedEx package (cuz they haven't yet entered into their system that I want them to just LEAVE packages like everyone else) after work and flip the book over and take out one of the 256 ram chips it shipped with, put in the new 512. I get all the cables hooked back up, restart, and I get a flashing folder/ question mark then a multilingual "hold down your power button to shut down now!" On the restart the machine starts despite this. What the heck? I haven't had a single problem with this machine. Could it be the RAM? Naw. Could I have done something goofy putting in? Naw. So I try to run my Norton CD on the OSX partition and it can't read the whole thing!!!!! Sumnuva _____!!!!! I reboot several more times from the cd and the OS9 partition try and clean up the drive. So then I get it working fine after a couple of hours. All the time i am thinking--oh it was probably because of some drivers or some bad software or something or too many mp3's or SOMEthing other than RAM. Well, since I am a(n) (idiotic) scientist I had to go and put the 512 in again. Hmmm, can you surmise what happened?!!!!??!?!?!?!? Well, i got the wierd screen with a dialogue box in like 12 languages telling me to hold the power button to shut down. Fantastic. I took the RAM out, replaced the 256 dimm and guess what? My machine is norm'd again. I guess you get what you pay for. Somebody at 18004MEMORY is gonna have a new one torn into 'em tomorrow, i tell you what. Just thought i might warn others out there looking for RAM upgrades. I know it's always buyer beware and others who wrote me had no problems with 18004 but after this experience I think I will trust others like Crucial or Kingston. +kevin