Macbook Panic CPU NVRM

Here is my accumulated links on the subject of disabling the Discrete GPU. GPU Disabler in the most stable for difficult situations, gfxcardstatus is the mildest for "it's only a problem occasionally". Read all before you act, this is a list not a procedure.

Install gfxCardStatus (https://gfx.io) and set it to "i" (integrated graphics only). It will allow your MBP to run on integrated graphics only, bypassing the discrete GPU which has the issues. This may allow your MBP to run normally, although it will have reduced graphics performance when permforming demanding graphics tasks. The alternative is replacing the logic board, which is not cost effective on a machine that old, unless gfx does not resolve the issue and you really want to keep this MBP.

There is an acknowledged bug in the current version of Cody Kreiger's Open-Source gfxcardstatus, and the developer has confessed he does not have time to fix it right now.

There is a fork off the main build by steveschow available that seems to fix that problem for current versions of MacOS such as ElCapitan and Sierra. He provides a finished .app for direct download -- you do not have to compile anything.

https://github.com/steveschow/gfxCardStatus/releases

Also note that if your Mac does not run long enough to allow gfxcardstatus to be added, this is not really practical.

In addition, Steve Schow writes that he has abandoned further development -- because there are better solutions available [for both the 2010 model and 2011 models].

2010 model:

I have discontinued use of gfxCardStatus to solve the MBP kernel panic problem as the issue is better solved on 2010 models with the nVidia GPU by the following hack:

https://github.com/julian-poidevin/MBPMid2010_GPUFix

2011 model:

the use of ArchLinux bootable CD to gain access to and re-write the EFI on the drive, and permanently disable the discrete graphics chip. This page and scroll down past the list to the blog:

http://github.com/steveschow/gfxCardStatus

There are two similar procedure listed. I used the second from MacRumors as it seemed easier. I have made the Arch Linux bootable CD on another Mac, and tried this approach. I now have a perfectly-functioning MacBook Pro late 2011 15-in model with Discrete Graphics disabled. Runs just fine. But NO external display support any more.

--------

There is a completely different hack developed more recently. It requires only single-User mode to get started, then type a complicated string into NVRAM, then disable System Integrity Protection and run an additional little program (direct-download link provided there) to make the change semi-permanent.

http://dosdude1.com/gpudisable/

If any of the links does not work immediately, copy and paste in a new window.

Disconnect the power adapter & the battery. Then connect the power adapter again & try powering on the laptop using just the power adapter. You may need to wait 30 seconds before pressing the power button (sometimes may require holding the button slightly longer than normal). Sometimes Apple laptops get into a weird state and the only way to power them on is to disconnect the battery. If it powers on, then reconnect the battery while the laptop is still running. If the battery is discharged, then let it charge to at least 10% before powering the laptop down or you could damage the battery. Just be careful not to have any of the open circuitry touch any conductive (aka metal) items or you will destroy the laptop. Putting the laptop on its side is an easy way to work on it.

Hi Apple Community,

I was trying to recover my old MBP (Mid 2012 15") today but unfortunately it won't boot up.. The screen stays black, the keyboard and the apple logo on the back of the notebook don't light up either. I found the following PANIC File in Library->Logs->DiagnosticReports:

<PANIC File.log>

If the MBP does not boot how did you extract the current panic report? That report is dated Thu May 17.

Typically a single panic report is not as meaningful as at least 3 reports posted in there own "Additional Text box" in this way analysis for a trend or non-trend is the most informative to go forward with a diagnosis

If I had to take a WAG I would say your GPU has failed.

In or out of warranty you can get a free over the counter 'Apple Service Diagnostics' test and ask specifically for the VST (Video Systems Test)

Make an appoinment

https://www.apple.com/retail/geniusbar/

https://checkcoverage.apple.com/

https://support.apple.com/my-support

https://support.apple.com/en-lamr/aasp-program

From iOS online Genius Bar appointment:

https://itunes.apple.com/us/app/apple-support/id1130498044?mt=8

The Discrete GPU in some of these dual graphics 15-in MacBooks sometimes gets really hot under load, and heat is the enemy of integrated circuit chips. Sometimes these Discrete graphics chips fail, and the system does not realize they are not viable, leading to a kernel panic.

Because the Integrated GPU is still available, hobbyists have developed a number ways to keep these Macs running, even if the Genius Bar says they cannot be fixed (strictly speaking, these are not fixes, they are work-arounds).

So if they tell you it's the Discrete GPU that is the problem, post back for a list of work-arounds.

Replacing the Logic Board is your best choice. Very few people are able to perform circuit board troubleshooting or soldering as it requires a schematic and a hot air station and detailed knowledge. Some vendors will repair your own Logic Board if you send it to them, but make sure they are a reputable vendor. Logic Board repairs typically cost around $300.

¿Even Option Boot?

If yes, then you will likely need to replace the logic board (containing BOTH GPUs) to get a picture again.

That is an interesting project, but a complicated project. Think hard about whether that is in your long term best interests (or whether you would have fun doing it).

The try the instructions for GPU Disabler, and boot into Single-User Mode (hold command and S as you start up).

GPU is fine (Safe Boot didn't show any effect/ SMC didn't show any effect)

Under what circumstances do you get a picture on any display?

Usually the first thing the Apple Store or an Apple Authorized repair center are supposed to do is run the Apple MRI diagnostic while the client is waiting since this test only takes a few minutes to run. I can understand they did not run the VST as suggested by leroydouglas if your laptop is not a 2011 model. Otherwise their diagnosis seems a bit premature unless they opened up the laptop to test the components unless you have a 2011 model which is considered Vintage by Apple.

What is the exact model of your laptop? You can get this information by entering your serial number here.