Hello, I need help with my a1286(MC723/A) 2.2GHz i7 early 2011. The unit will turn on , chimes are heard, fan spinning hard drive spins normal start. But the display is pitch black. Unable to see anything with a flash light when shine to the screen. I connect the laptop to a external monitor. On the external monitor it boot to the white screen with apple logo and the spinning gear, that's it, won't boot past the white screen. Replace the display and display cable(both new) still black screen. I have also replace the ram with new ones, still the same problem.I am also planning to change to new HD and install snow leopard 10.6.6 (DVD black disk) Oh I forgot to mention that I had tried all start up combination keys from apple support, nothing works, If all else fails I do not know what else to try. If anyone has experienced this kind of technical problem, please help I do not want to go down the road to getting a new logic board, this a very expensive way. Thanks with a thousand gratitudes.