Hello all, I am having a problem with my 15" Macbook Pro. It is an older model (about 2005), running 10.4.11. This problem started when I was on Firefox browsing Hulu one day. The computer froze and the rainbow gear wheel started spinning and a little ladder like symbol replaced the mouse pointer. So I shut it down and turned it on again. Five minutes later, the same thing happened. This time, when I tried to start it up, it got stuck on the blue screen right before the loading bar and after the first grayish/white one. This would happen every time I turned it on, until I brought it to the Apple Store. After a lot of testing, the store rep decided it was a RAM problem (about a year ago I had replaced the 1gb RAM stick with two 1gb sticks from Crucial). We took one of the sticks out and it worked perfectly, albeit a little slow due to the 1gm of RAM. I brought it home, and after about a week of use, the same problem started happening again. I do not know what to do now, because when I switch out the RAM it doesn't fix it this time. So can you guys please help with this issue? I'll be happy to provide more info if needed.