Laptop Strange behaviour

[ianniow]

I was asked to look at the problem of the headmasters laptop (had to be his)
During boot up it gives all the symptoms of the back light not working, ie screen very dark can just about see that it is booting up.
If you wait and can just about see the "Press Ctrl alt Del....to logon" then logon to the network.
Once the user profile comes up suddenly the light gets turned on and all is well.
I have tried to get an external monitor so that I can get into and see the bios but no avail. Bios only appears on the laptop screen.
Any ideas
Oh its a Toshiba Satellite Pro
Win xp

[witch]

Once the backlight comes on - does it stay on for a long time? We had one with the same problem but the light faded again after a couple of hours.
It was the invertor apparently

[ianniow]

No everything seems to be fine it has been working since yesterday morning, head did not turn it off last night.

[kmount]

Tried the brightness adjuster keys on the laptop itself just incase?

[ianniow]

If you mean the fn +f6 or f7 then yes but they have no effect while booting