System install was a success and was able to restart machine B successfully from the hard drive of the faulty machine. put the back on, use just a few screws to hold it. GENTLY remove the RAM DIMMs, clean the contacts, then re-seat them. Make a drawing ON PAPER so you know 'where the long screws go back to'. Did a clean system install from machine B (while still in target disk mode). take the back panel off (you need a Phillips -00 driver). Hard drive checks out with no errors and is formatted in Extended Journaled. DVD spins up but then three beeps.įired the machine up as a target disk and ran disk utility via remote control from another machine, we''ll call that one 'machine B'.

Perhaps the ROM was corrupted by some electrical damage involving the ROM chip and circuitry.

The ROM instructions for booting your computer will not function to startup the computer. A POST with four beeps is a bit more serious. Bought new ram, put it in, reseated it a bunch of times, still three beeps every time.Īttempting to restart using the system DVD by holding the C key, same problem. Reseat the RAM modules and also reset the PRAM (parameter memory) on the MacBook Pro. Computer starts with normal chimes, then when it gets to the grey screen with the Apple, I get the 'three beeps'. Now I can't get as far as the password screen any more. E177FP monitor to a DeLL 520 with XP Pro 64 bit and Dell 745 with XP Pro. So I attempted to boot from my own Snow Leopard DVD, then I started getting three beep errors. quad-core chipset runs at 3 The maximum amount of memory you can install. I thought this was going to be an easy case of erase-and-install. My friend did not have the password to get into the machine and no original system disc. They were given the computer by someone who didn't want it. I'm working on a Macbook pro 15 A1278 for a friend.

Macbook pro 3 beeps reseat ram