Hi There, I recently bought a second hand macbook pro from a friend, after having the computer for 1 day I started to get problems. Sometimes when I go to turn it on, it begins to sound like a fan starting up inside and the light on the latch button comes on for about 3 seconds then the computer turns off. Nothing comes up on the screen. I tried removing the battery, and using only the power lead, I tried using only the battery and not the power lead, I removed each stick of ram and then re-inserted it to see if either of them were the problems, but it continued to make the fan sound, and the light would come on, but only for three seconds. I went outside and began to get upset, but when I came back in and tried it again it started up perfectly. The same problem persists every second or third time in a row that I try to start it up. Sometimes it wont start up for several minutes, other times it only takes me pushing the button 1 or 2 times. Please help me, I am so worried!!!