Alcione

I have an msi gt70 (i7 3610QM) notebook that wont power up. it shut down in the middle of doing something. Now when I go to power it up the power button flashes white once then nothing happens. Battery is fully charged and have tried it with and without battery installed. voltage from mains power supply is ok. Anyone else had this problem? Anyone know how to fix it? Before you ask, nothing had changed for many days in config or installed software etc. Its only 3mths out of warranty! thanks