Repair shop suggests to solder new graphics chip onto a used graphics card Recently, my 27" iMac Mid-2011 had a graphics card failure (an AMD Radeon HD 6970M 2GB GDDR5).

Even though the computer now is vintage-classed, I still want to repair it. Unfortunately, Apple-authorized service partners are not allowed to service vintage-classed computers, so I had to turn it in to an unauthorized service shop.

The service technician claims to have found a used ATI HD 6970M 1GB from some secondary market supplier online. Since the card is used, he recommends that the supplier solders a new non-used ATI chip of the same type onto the graphics card board.

I have never heard of this procedure before and I am unsure if this is a recommendable idea. My concerns are are mainly if this is:


(A) At all recommendable to cushion against chip failures of a used card.
(B) If there are any safety concerns (e.g. electricity risks) due to doing this.




(The cost of the soldering operation is not a major concern although it has bearing, he says the soldering of the new chip will be $35 USD, added to the price of the used card which sells for $520 USD).
Speaking from experiences in the repair community: Its unlikely that its actually a new unused chip. A lot of sellers try to find working chips and clean them and brand them as new. (Some even going as far as lasering in a new date code to make them look like they came from a recent batch, even though the chip has not been produced for a while).

Even if the graphics chip would be new it has the same design faults in there that made it die in the first place. That combined with being unsure about the practices, heat settings and how the chip was stored makes it very uncertain for how long it will last. 

My advice: If the store is willing to do this for less then $80 you might want to give it a try (while also saving up for a new device), higher then that and I personally wouldn't risk it.

To answer your second question, there aren't many safety concerns. If a graphics chip shorts out the system will just disable power. I would say the electrical risk is close to none and not more then it has always been