CMIzapper  Technology for your Mac repair business

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Tiresias (the GPUkiller)

The Tiresias is a small board that can be soldered onto the motherboard of the MacBook Pro 15-inch or 17-inch 2011 (Early or Late) models.

These are all the models that have the 820-2914-A, 820-2914-B, 820-2915-A or 820-2915-B motherboard.

The 820-2914 and 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 820-2914 or 820-2915 with dead GPU back to life. Installation is easy (no wires to solder). 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.

Mac OS X 10.13 High Sierra is also supported! To have brightness control in High Sierra requires soldering two extra wires from the Tiresias to the motherboard. So any (!) OS supported by the Mac will work (10.6 - 10.13).

See our page with Technical Details. Mounting instructions 820-2914. Mounting instructions 820-2915.

Tiresias for 820-2915 (15-Inch)

Quantity one (1)

Including shipping (world wide)

60 EURO.

Tiresias for 820-2915 (15-Inch)

Quantity three (3)

Including shipping (world wide)

120 EURO.

The Tiresias GPUkiller mounted over the ROM on the 820-2915.

The Tiresias GPUkiller for the 820-2915.

Tiresias for 820-2915 (15-Inch)

Quantity five (5)

Including shipping (world wide)

160 EURO.

Tiresias for 820-2914 (17-Inch)

Quantity one (1)

Including shipping (world wide)

60 EURO.

Tiresias for 820-2914 (17-Inch)

Quantity three (3)

Including shipping (world wide)

120 EURO.

Tiresias for 820-2914 (17-Inch)

Quantity five (5)

Including shipping (world wide)

160 EURO.

The Tiresias GPUkiller mounted over the ROM on the 820-2914.

The Tiresias GPUkiller for the 820-2914.

Bulk pricing

If you buy larger quantities of the Tiresias the price drops.

From quantity 10 or up you can mix and match between the 15-Inch and the 17-Inch model. Please send us an email immediately after placing the order telling us how many of each kind you would like.

All prices include shipping world wide.

Tiresias for 820-2914 / 2915 Quantity ten (10)

295 EURO. (29.50 euro each)

Tiresias for 820-2914 / 2915 Quantity twenty (20)

560 EURO. (28 euro each)

Tiresias for 820-2914 / 2915 Quantity thirty (30)

810 EURO. (27 euro each)

For larger quantities see our bulk pricing below.

For larger quantities see our bulk pricing below.

If you are looking for larger quantities please contact us.