Tosh Satellite Display Problems (software?)

Here's a problem which has shown up in the last couple of days.

My son has a Toshiba Sattelite - not sure which model. As of a few days ago, following power-up, when the Toshiba ad and Windows loading logo show up (briefly) as normal, the screen then goes completely dark, with text & graphics just barely visible - in some lights it is possible to see the icons/ pointer and perform a re-start, but the problem persists.

I've read helpful posts re ballasts/ inverters and pin connections. Although the symptoms are similar, I've got a strong feeling that this is a software problem as the Toshiba ad and Windows loading logo show up (briefly) as normal, brightly, following power up. We've tried the external/internal screen thing (Alt/F5) without success, and I don't think it's a password issue as we can operate the thing with difficulty in certain light conditions.

Any ideas out there? All advice gratefully received :smile:

Ayrton