MacBook Pro 2011 (15 inch) Tiresias GPUkiller for 820-2915. Solves GPU problems.

Description

Tiresias (the GPUkiller) as produces by CMIzapper.
You are buying one (1) Tiresias for the 820-2915 (
820-2915-A or 820-2915-B)
. This will fix a MacBook Pro 2011 (Early or Late) which has a GPU problem, by turning off the GPU. You will have to solder it to the motherboard as well as remove one resistor from the motherboard. A good soldering skill is required!
The Tiresias is a small board that can be soldered onto the motherboard of the MacBook Pro 15-inch 2011 (Early or Late) models.
These are all the models that have the 820-2915-A or 820-2915-B motherboard.
The 820-2915 board has two GPUs. The internal (Intel) GPU that is part of the PCH, and an external (discrete) AMD GPU. It is the external GPU that fails  in 'a small percentage of MacBook Pro systems' (Apple-speak for: 'very many'). The Tiresias writes the 'gpu-power-prefs' nvram-variable to the ROM so that the Mac does not use the (dead) external (discrete) AMD GPU anymore. If the user clears the NVRAM (PRAM) there is no problem as the Tiresias will write the record again, and the Mac will work again.
This makes this the ideal solution to bring a 820-2915 with dead GPU back to life. Installation is easy. You will need to mount a very small board onto the motherboard. An experienced technician can do this in minutes. Other than that R8911 should be removed to turn off power to the dead GPU. This saves energy, generating less heat and conserving battery life. Removing R8911 also prevents the Mac from getting confused by the dead GPU because even with the GPU turned off it will still try to talk to the dead GPU. Depending on what internal contacts in the GPU are ruptured this might confuse or even crash the Mac.