My mac randomly shut down (power off)

hello. sorry for my english.

i was watching some youtube videos last day and my laptop suddenly shut down.

i tryed to restart but led indicator was iluminated for a bit, but the mac didnt start.

i pushed power button for 3-4 seconds and and laptop started.

i realized thant my laptop wasnt so fast as usual so i tested with geekbech and what was my surprise that score was half that normally.

my configuration is owc SSD 6g + WD scorpio black 750gb.

maybe is this the problem? or maybe left i/o board?

i uploaded a video to youtube.

http://www.youtube.com/watch?v=YCZBs2TAZ...

now the laptos is working fine anfter i reinstalled today mountain lion but sometimes freeze a lil (spin ball with safari)

thank you in advance!!

i forgot to say when i start my system (osx mountain lion) the menubar is hidden till i click on some apps.