sony vaio vpc ee31x white screen

I have a year sony vaio ee31x laptop, more than a month ago My screen would go white either when I am working on the laptop or when booting up, then it would show after a few mintues and the go white again. I recovered my laptop and it worked fine for another five weeks. On Friday the 16th of March the white screen problem started again. I tried recovery with no avail. I was adviced to test it by connecting a monitor to determine whether it was the lcd display intermitter. When I try connecting to an external monitor nothing is happening.

Please help