My notebook's screen froze when i was playing game. i closed notebook with pressing power button. and then i can't open it. i just see black screen. i know the problem but i don't know how i can fix it. it's about ram slots. a few months ago i saw this problem. i removed second ram and notebook worked fine. after that i removed first ram and i put it second ram slot and notebook didn't work. the problem is about second ram slot. when i put a ram into second slot i saw only black screen. a few months i used my notebook with one ram(2gb). and today i have same problem again. now first ram slot is not working. i don't know why this is happened. i was just playing game and why ram slots are not working.. is there any way to fix ram slots or must i change mainboard with a new one?