I installed Mavericks (upgrading from Mountain Lion) on my MacBook Pro (from early 2011) and the install seemed to go fine. However, this morning while I was working on PowerPoint, it switched off with no warning at all (it was connected to AC power and battery was full). Then, it refused to boot. After the spinning bar under the logo, it just gave a gray screen and was completely unresponsive. I tried to boot into safe mode by pressing ⇧ shift while booting and it reached a blue screen with vertical black stripes and was again unresponsive.
Then I tried clearing the NVRAM with ⌘⌥PR and it again reached an unresponsive gray or blue screen if I waited long enough. Tried Internet Recovery but after downloading something for an hour it again gave the blue screen with vertical stripes.
Any idea what I can do? Can I use a Linux LiveDVD or something to extract some data I have on it?
ETA: Ran the hardware test from the included Applications DVD and it did not find any troubles. Trying to boot with a LiveDVD did not work. Did get to the stage where I select from the range of boot options but then the boot did not complete. Tried with Ubuntu and CentOS.