Model A1312 / Mid 2011 / 2.7 & 3.1 GHz Core i5 or 3.4 GHz Core i7 Processor, ID iMac12,2

452 Questions View all

Upgrade from 6770 to 6970 is possible?

I have a 27" mid 2011 iMac.

Originally it has a core i5 processor and an HD6770M gpu

I' wondering if I can replace the gpu with an original HD6970M

Do you have any idea?

Answered! View the answer I have this problem too

Is this a good question?

Score 0
Add a comment
Spread Fixmas Cheer
Get $12 off your purchase of $50 or more with code FIXMAS12
Spread Fixmas Cheer
Get $12 off your purchase of $50 or more with code FIXMAS12

1 Answer

Chosen Solution

Here are your three GPU choices:

  • AMD Radeon HD 6770 (512 MB) - Apple P/N 661-5967
  • AMD Radeon HD 6970 (1 GB) - Apple P/N 661-5968
  • AMD Radeon HD 6970 (2 GB) - Apple P/N 661-5969

We don't have a direct guide to replace the GPU in this series but this IFIXIT guide you'll get you mostly there: Installing iMac Intel 27" EMC 2429 Dual Hard Drive Kit. Go through the steps to Step 31 at which point you'll need to disconnect the SATA & power cables of your drives to finish freeing up the logic board. Once you get the board out you'll need to dismount the GPU board with its heatsink.

If your system is working now you may want to think twice here on this swap out.

First: You will need a real Apple GPU board as the boards firmware is custom.

Second: It's a lot of work and the amount of improvement may not be what you expected unless you also upgrade the systems CPU to an i7 as well. So if that is what you are also intending on doing I would first do it making sure the system is working with the new CPU before going to the expense of replacing the GPU in case you have problems in the process (change out one thing at a time).

Was this answer helpful?

Score 3


Thanks for your answer!!! Really complete :)

I have a concern. It seems the 6970 is one inch bigger than the 6770.

I guess there are 2 solutions

1.) replace the HD for an SSD

2.) replace the heatsink

Is this really a big problem?.

Btw. My mac is running, but I'd like to improve the gpu since I will use it for modeling and rendering

In your opinion. This upgrade worth the effort?


The parts I listed are the boards Apple used in this series of systems. There is no physical issues using these exact boards.

If you got the board off of a different system you will need to swap out the heat sink (and refresh the thermal paste & pads) and you may still have a problem as the board needs to be an Apple version otherwise the board won't work correctly in the system.

I think I would start off replacing the CPU to an 3.4 GHz Core i7 (I7-2600) first. Modeling as well as rendering tend to be more CPU intensive than GPU. It's only the displaying of the work does the GPU get used heavily.


I ordered this one

It seems is a used original GPU

I guess I will need to replace the thermal paste as you described.

(I ordered an Artic Silver 5, I wasn't´t aware I need to replace thermal pads D: )

I will update the post with photos of the process.

Thanks for your assistance, I really appreciate that :)


It's the proper way to deal with the RAM modules. make sure you do a dry fit to test the thickness of the pads (get a set of different thicknesses). You want a snug not tight fit as the part heat up things do expand. Don't forget to take both cover tapes off (top & bottom of the cut out pad and don't touch the surfaces as the dirt and oils you have on your hands will effect the heat transmission.

Apple went cheap on the last versions using a gapping thermal paste which I have not been able to replicate. Use care removing the black insulator as they are not flexible (from age).


Well, I have not replaced anything yet (all the items are in transit)

Once I begin with the process I will let you know for record purposes. Maybe other people find this useful.

Thanks for your support :D


Show 2 more comments

Add a comment

Add your answer

frankgumeta will be eternally grateful.
View Statistics:

Past 24 Hours: 2

Past 7 Days: 4

Past 30 Days: 16

All Time: 294