Whats wrong with my Acer Aspire?

I have an Acer Aspire 4315. It's running Windows Vista and the Acer Empowering Technology stuff. I've had it for almost two years. It usually runs really smoothly but sometimes the screen will just randomly go completely white. It's still working (like if I'm playing music before it happens the music will still play) but the I can't see anything at all. I can't figure out whats wrong with it. I'm considering just breaking down and buying a new laptop but I'd like to avoid it if I can fix my current one. Any suggestions?