2014 MacBook does not boot; 2 chimes My MacBook experiences boot up problem.

A normal MacBook could startup properly after pressing the power button and a chime sound would be heard.

But my MacBook (2014 Mid MacBook Pro with Nvidia graphic card) is a different story. After I pressed the power button, I would hear 2 chime sound and the screen is not turning on. I have to force shut down and reboot again. Then everything seems OK again. 

This is really frustrating, it happens every time I shut down or sleep my device.

System report from MacBook

panic(cpu 0 caller 0xffffff7f842be679): GPU Panic: mux-regs 2 3 5f 1d 0 8 severity 3 WS-ready 1 switch-state 0 IG FBs 1 EG FBs 0:0 power-state 4 3D idle HDA idle : NVRM[0/1:0:0]: Read Error 0x00137310: CFG 0x0fc910de 0x00100000 0x00000000, BAR0 0xc0000000 0xffffff9214f8f000 0x0e7290a2, D3, P0/4
Reset NVRAM or PRAM on your Mac

Settings that can be stored in NVRAM include sound volume, display resolution, startup disk selection, time zone, and recent kernel panic information. The settings stored in NVRAM depend on your Mac and the devices that you're using with your Mac.

Shut down your Mac, then turn it on and immediately press and hold these four keys together: Option, Command, P, and R. You can release the keys after about 20 seconds, during which your Mac might appear to restart.

I also would suggest you try SMC Reset if the above solution doesn't help. 

Reset the SMC on Mac

First, shut down your Mac and Press Shift-Control-Option on the left side of the built-in keyboard, then press the power button at the same time. Hold these keys and the power button for 10 seconds. Release all keys. And, Press the power button again to turn on your Mac.

What the SMC does

The SMC is responsible for these and other low-level functions on Intel-based Mac computers:


Responding to presses of the power button
Responding to the display lid opening and closing on Mac notebooks


For more reason, you can check https://support.apple.com/en-us/HT201295