osx acting wierd


Ok I have osx tiger installed on my ibook. One day I decided to swap rams and booted ibook. Ok it booted fine but right when it logged in it started acting wierd. First it never launched the dock or anything else. After a little while there is a spining thing on the bottom of screen. Its the thing when u shut down, this circle starts rotating or something. Well it did that and eventually it shuts down. So I put the orignal ram back and still has the same problem.

After restarting several times, now after the bootup screen, I goes into text mode and asks for my username and password. I can login fine with that but I dunno how to get the desktop to come up. So I just exit that text mode. It shows mthe desktop background but the spinning circle comes up on the bottom getting ready to shutdown. So it keeps doing that now. Is there any way to fix this problem? I tried reseting nvram and reseting everything but didnt work.

Any way to fix it?