My Toshiba Tecra M10 Model PTMBA-04S001 boots to the Toshiba start screen for about 1 second then goes black. The machine continues to boot to Vista but iut just shows a black screen. If I connect it to an external monitor, it acts normally, however, when switching back to the laptop screen, it displays for 1 second, then black. I have checked the inverter, which is okay. Prior to this problem occurring, the botton left hand corner of the screen showed a black "bloom" about 20mm in diameter and the screen got very hot in this section. By hot I mean around 90 deg Celsius. I am thinking that the LCD is crook by I need a way of confirming this prior to purchasing another LCD. Any suggestions will be gratefully received.