NEWS FLASH for MacBook Air users with 3 Beeps at startup!!! On a hunch, as I have noticed my MacBook Air has overheated in the past, I opened mine up to check the THERMAL PASTE. Made no sense that DRAM of any sort would fail after 15 months. When I got down to the logic board, I inspected the 8 visible 1 gigabit chips visible. The solder joints appeared pristine. Nothing else appeared burned, fractured, loose or disconnected. I then removed the heatsink I found the thermal paste dried and hardened! I carefully removed all of the old paste and then applied new high quality thermal paste. I then reassembled the machine. Rebooted and NO 3 beeps! Once again, my MacBook Air appears to be working perfectly. Therefore, if you have recently had a MacBook Air exhibit the 3 beep boot failure, strongly consider checking your thermal paste. WARNING: You should do this ONLY you are an experienced repair person, and only if your computer is already out of warranty. FYI: I've been building, repairing and modding...
IMPORTANT NOTE REGARDING ZIF CONNECTOR: The cable can be removed in the locked position [not recommended]. However, when reinserting the cable, if the ZIF connector is not unlocked, the connection WILL NOT FUNCTION! This is a possible fail point and reason for ending up with an LCD screen that doesn't work in an otherwise functioning iPad. Be certain that the ZIF connector is unlocked prior to reinserting the cable contact. MAKE ABSOLUTELY SURE TO FLIP BACK DOWN AND RE-ENGAGE [Lock] the ZIF Connecting clip after reinstalling the cable connector. This comment applies to ALL 3 ZIF connectors [2 for digitizer, 1 for LCD].