When I bought my Macbook, I got the standard 512 MB of RAM. I recently purchased 2 GB of RAM from OWC. I followed the instructions and got it installed. I then went to boot my Macbook and got the white screen with the gray Apple logo and the spinner. It never left that screen. After trying a lot of things, I did a reinstall of Tiger using the Archive & Install option and that worked. I checked the System Profiler and confirmed that it saw the 2 GB of RAM. I did all of the Software Updates (including the 10.4.7 update) and everything seemed fine. I went to reboot later, and got the same white screen with the spinner and it never made it past it. I again tried a lot of things. Sometimes I'd get the white screen with spinner, sometimes I'd get "verbose mode" (without initiating it) and would get errors about "com.apple.nibindd" spawning to quickly. I found these instructions on how to clear caches/.plist files. If I booted into Safe Mode, followed those instructions, then rebooted, it was fine. However, the next time I rebooted, I'd get the same problems back. Last night, I backed up everything and did an Erase & Install. Again, everything seemed fine. I rebooted a couple of times and everything seemed okay. I then went out and manually downloaded and installed the 10.4.7 Combo Updater. Now, I have the same problems again except now, I only get the errors about "com.apple.nibindd" spawning to quickly. It would seem that 10.4.7 is what's causing my problems. However, I was running 10.4.7 before upgrading the RAM without any problems. Why is it different now? If the RAM was the problem, why would it boot fine in Safe Mode and work fine once after removing cache and .plist files?