iPod Touch 3g White Screen, What Part Could Be Deffective?

Every time I try to turn my iPod 3g on I am greeted with a white screen, known as the white screen of death. I know there are many possible reasons for this, but it's not a software issue, it's fully recognised in iTunes. I'm wondering is it more likely to be the didgitizer or the lcd display? So I know which one to replace.

Thank You.