Sony k23 Grahpics Drive Display issues HELP

Working on a customer's k23 Sony Viao,

Thought he had a bad backlight in his LCD so I replaced it. Put the new screen in and had the Same issue when i boot into windows no backlight The backlight shows a post screen and bios screen but as soon as i get the loading bar for windows the backlight goes.

So I of course i thought, bad backlight again on the new pannel so I plugged a dif in without booting into windows, stayed on, rebooted to go to windows as soon as the windows bar came clicked off... hmmm

He's the kicker when I use linux bootdisk on the machine, the backlight does not fail, it stays on no issues.

The backlight will also go out when i load in safe mode, and i also tried to boot into a ERD and a Herins mini boot, same issue

Tried removing the graphics drivers still no success.

Im trying a reload of the machine at the moment on a spare hdd will let you know how that goes,

Anyone any ideas,

Ati ghx card 385 in the machine

Thanks

Cope