MacBook Reboot Problem

Hi Guys! I'm not sure if this is a hardware or software problem, but I dared to post it under hardware. I'm sorry if this is a mistake.

While installing Google Chrome beta, my laptop froze. I forced it to shut down, then turned it on. Upon reboot, it displayed the blue screen. Forced shut down again, twice. After reboot, I was prompted to enter my password. Funny thing is, I disabled the login screen a day before that. Still, I entered my password. Password accepted, but after a while, it prompted me to type in my password again.

I can shut it down, restart or make it sleep from the login screen. I tried to reboot on safe mode, but it did the same thing. I followed the troubleshooting steps found in Apple Support like fsck, etc to no avail. The problem is, my MacBook is second hand and I don't have a start up disk. What can I do next?

Well, it's difficult to really pin-point your technical issue without physically being in front of the Mac. My best advice is to take it to your local Apple Store and see what they will do to help. They are often very kind regarding assisting their customers.