Replacement psu turned up, laptop now powers up but screen is black. Plugging into external monitor makes no difference so guess the gfx card is shot..not cheap to replace argh :/
remove battery and power cable hold down power for 10 secs ... leave battery out and just apply mains power then try turning on .. if it boots fine to windows insert battery .
if its a card on a board.. pop it out and remove plastic/rubber and pop it in the oven for 20 mins (220) .. leave to coo and refit plastic/metal parts and refit