Main characteristics of BSOD and GSOD
BSOD (Blue Screen Of Death): You have pressed the power button of your MacBook Pro and the computer starts normally. Everything looks good so far: the automatic self-test passes successfully, the startup drive has been detected, and the MacBook Pro starts loading. And continue loading, and continue loading, and… More than ten minutes have passed, but the only thing that is displayed on the LCD of your MacBook Pro is the blue loading screen. Well, that’s the so called Blue Screen Of Death. A great start of your day, right?
GSOD (Gray Screen Of Death): Almost identical to the BSOD, but this time the blue screen disappears, and then a blank gray screen appears. 10 minutes later everything is still gray, and after another 10 minutes, and… That’s the main characteristic of the Gray Screen Of Death.
Possible Causes and Solutions
You should check your main HDD/SSD, also referred as the startup drive, for bad sectors, file system errors, etc… You can accomplish this task by using the built-in Apple disk utility, TechTool, DriveRepair, or other disk repair/management software. Once the program finishes scanning and repairing your startup drive, you should start the MacBook Pro and check if everything loads normally. Continue reading if you once again get stuck on blue or gray.
Try using a different mode
In some situations, you can fix the BSOD or GSOD issue by changing the mode. You should try starting your Mac Book Pro under Verbose (cmd + V), Single-user (cmd + S), or Safe Mode (Shift). Run a full virus and system error scan if you succeed logging in. You should also make sure that the startup drive permissions are properly setup.
Corrupted OS installation
It is possible that some of the system files of your OS are missing or corrupted. This could be due to a virus infection, bad HDD sectors, improper shut down, etc… The most effective method to solve this is to reinstall your OS X.
A bad stick of RAM
Use a RAM testing program, such as MemTest, in order to make sure that the RAM modules installed in your MacBook Pro are not failing. The new RAM modules are really cheap nowadays, and you can even upgrade your PC with up to 16GB of RAM for less than 200$.
Dying Logic Board
This is the worst case scenario. The regular Mac user won’t be able to fix the logic board completely by himself. We have heard of a guy who has baked his MacBook Pro in an oven at 170degrees in order to restore the solder joints of the logic board. However, we strongly recommend against such actions. The wise thing to do is to take your MacBook Pro back to the dealer, or send it to the nearest authorized repair shop for service. Please leave a comment if you have a better solution.