Macbook pro 15 early 2011 logic board failure.

If you have a grey screen on boot, have you followed this Apple note? When you get to the part where it says to insert a disk to boot and run Disk Utility, you want to boot into recovery mode by booting and holding the command and r keys down. It would be handy if you have a bootable backup to use if booting into OS X recovery doesn't work.

If you've been told by a reputable service provider that the logic board has failed, then the only thing you can do is to replace it. Otherwise take each of these steps that you haven't already tried. Stop when the problem is resolved.

b. If you have access to a working Mac, and both it and the non-working Mac have FireWire or Thunderbolt ports, boot the non-working Mac in target disk mode. Use the working Mac to copy the data to another drive. This technique won't work with USB, Ethernet, Wi-Fi, or Bluetooth.

c. If the internal drive of the non-working Mac is user-replaceable, remove it and mount it in an external enclosure or drive dock. Use another Mac to copy the data.

Step 2

Press and hold the power button until the power shuts off. Disconnect all wired peripherals except those needed to boot, and remove all aftermarket expansion cards. Use a different keyboard and/or mouse, if those devices are wired. If you can boot now, one of the devices you disconnected, or a combination of them, is causing the problem. Finding out which one is a process of elimination.

If you've booted from an external storage device, make sure that your internal boot volume is selected in the Startup Disk pane of System Preferences.

Step 3

Boot in safe mode. Note: If FileVault is enabled, or if a firmware password is set, or if the boot volume is a software RAID, you can’t do this. Post for further instructions.

Safe mode is much slower to boot and run than normal, and some things won’t work at all, including wireless networking on certain Macs.

The login screen appears even if you usually log in automatically. You must know your login password in order to log in. If you’ve forgotten the password, you will need to reset it before you begin.

When you boot in safe mode, it's normal to see a dark gray progress bar on a light gray background. If the progress bar gets stuck for more than a few minutes, or if the system shuts down automatically while the progress bar is displayed, your boot volume is damaged and the drive is probably malfunctioning. In that case, go to step 5.

If you can boot and log in now, empty the Trash, and then open the Finder Info window on your boot volume ("Macintosh HD," unless you gave it a different name.) Check that you have at least 9 GB of available space, as shown in the window. If you don't, copy as many files as necessary to another volume (not another folder on the same volume) and delete the originals. Deletion isn't complete until you empty the Trash again. Do this until the available space is more than 9 GB. Then reboot as usual (i.e., not in safe mode.)

If the boot process hangs again, the problem is likely caused by a third-party system modification that you installed. Post for further instructions.

Step 4

Sometimes a boot failure can be resolved by resetting the NVRAM.

Step 5

Launch Disk Utility in Recovery mode (see Step 1.) Select your startup volume, then run Repair Disk. If any problems are found, repeat until clear. If Disk Utility reports that the volume can't be repaired, the drive has malfunctioned and should be replaced. You might choose to tolerate one such malfunction in the life of the drive. In that case, erase the volume and restore from a backup. If the same thing ever happens again, replace the drive immediately.

This is one of the rare situations in which you should also run Repair Permissions, ignoring the false warnings it may produce. Look for the line "Permissions repair complete" at the end of the output. Then reboot as usual.

Step 6

Reinstall the OS. If your Mac was upgraded from an older version of OS X, you’ll need the Apple ID and password you used to upgrade.

Step 7

Repeat step 6, but this time erase the boot volume in Disk Utility before installing. The system should automatically reboot into the Setup Assistant. Follow the prompts to transfer your data from a backup.

Step 8

A dead logic-board battery in a Mac Pro can cause a gray screen at boot. Typically the boot failure will be preceded by loss of the startup disk and system clock settings. See the user manual for replacement instructions.

Step 9

If you get this far, you're probably dealing with a hardware fault. Make a "Genius" appointment at an Apple Store to have the machine tested.

@migcabreraApple 2011 logic board had issues. Check the kb article http://support.apple.com/kb/TS2377 if you are facing this problem than apple may replace you logic board for free..

I took my early 2011 macbook pro i7 into Apple. I was offered flat rate depot repair for $310 and jumped at it. It came back looking new in a week. They replaced the logic board, RAM, and the basel. WIthin two months it failed again. Apple sent it off for repair for no charge (90 day warranty on repairs). I received it back working again, with a third logic board. It failed within two days. I returned it to Apple. The store manager sent it off for repair again, offered to and refunded the amount I paid for repair. So I could use it to buy something to work with. He said said it would have a 90 day warranty after being repaired! He said it would go for a higher level of repair. This will be the third repair attempt.

So I bought a new 11" macbook air.

I'm thinking something is killing the logic boards. In this video, of a different unibody repair, a short was found.
http://www.youtube.com/watch?v=DtHCv8HkNMU