I've got the same problem too. I managed to get the phone into download mode (the screen didn't show a thing, but Odin recognized it as "ADDED"). Flahsed an official ICS ROM, but the screen keeps black, but the initialization sound can be heard, and the phone still rings when receiving a call!
Dead hardware...I supose...
I have the same problem as you, but this is something I found out yesterday:
If you go to a dark room, and you turn on your S2, you can see some sort of.. light black/grayish pixel spots over your screen. It is pretty hard to see, that's why you need to be in a dark room.
Did anyone else notice this, or am I the only one?
As an update, I plugged the non working screen into a working S2, and it showed the Samsung logo on boot up. Then it went black again, but it can still show images, and did it multiple times. So the LCD works, but something is messing it up.
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