My macbook (OS X 5.5) is having some start up problems. It will get a gray screen that pops up and locks up my computer. It will say that your computer needs to be restarted. So i will restart it and then the load screen will come up and the dial turns and then it will just shut off. It will do this every time i try and start it back up. I took my computer into Apple and they ran Disk Warrior on it and that fixed the problem that time. Then a week later the same thing happened. I called Apple this time and told them the situation. They said it sounded like my hard drive was going out. So i sent my computer in and got a new hard drive. It came back and i loaded everything off of my hard drive back onto my computer. Seemed to be working fine. Then a week or so later the same thing happened. So I ran disk warrior on it again. It fixed the problem for about two days this time. I ran disk warrior on it AGAIN. I have no idea what is wrong with it. Does anyone have and ideas of what it could be? I should also say that I had bought some third party RAM off of a friend and put that in there. Apple said it COULD be the ram. I wanted to see what other people thought before i spent 130 bucks on Apple Ram and that end up not being the problem. PLEASE HELP!!