i got this mbp, approx 2 yrs old, that, apparently after having been in sleep mode for a while, now has no screen anymore (well, it has but it stays dark). no updates, no sw installs were made before that. when switching on, the chime sounds, but nothing else happens. now, i reset the pram, the smc, left it without battery overnight, tried the 'push the power button for 5secs without battery', tried connecting it to an external tft...nothing... warranty is expired...now before the owner goes to pay big bucks at the apple store for having it looked at...any other ideas what else we could try? thank you.