GPU Upgrade capability for Mid 2011 21.5" iMac.

Wow you have big ideas!

Let’s start off with the RAM just because you can push the system to 32 GB does your work flow really need it? People often forget you can go to low as well as too big! Consider what you are doing before making this investment. 16 GB tends to be the sweet spot for most folks!

CPU’s - Just because Intel stuck with the LGA1155 socket doesn’t mean your system has the needed power and cooling to support more powerful CPU’s and the systems firmware may not support it!

This series supports Intels Sandy Bridge series CPU’s so you are really limited to them. The most powerful this series supported was 21.5” iMac Core i7 2.8 GHz and the CPU its self Intel Core i7-2600S Processor Note the TDP is only 65 W

You are limited to 65 W chips. So from your list:

• Intel Core i7-3770S Processor - Ivy Bridge TDP 65 W but the systems firmware may not offer support for Ivy Bridge CPUs (not have the needed micro code).
• Intel Xeon Processor E3-1290 TDP is too high at 95W and missing the needed onboard graphics services iMac’s need. Won’t work
• Intel Xeon Processor E3-1290 v2 TDP is too high at 87 W and missing the needed onboard graphics services iMac’s need. Won’t work
• Intel Core i7-2600 Processor TDP is too high at 95W. Use the Core i7-2600S Processor!

GPU’s - This series often burn’t out the original GPU’s both because people pushed them beyond what Apple and AMD (ATI) expected pope would do. This gets into staring into the crystal ball years earlier. Trying to project what apps and people will need three and four years into the future! Well… They undershot what people needed. Again we hit the thermal limits of the systems cooling. So we are limited on what the heatsink and radiator can castoff.

So looking at the best GPU this system offered AMD Radeon HD 6770M we can see the TDP is 35. Sadly Apple also customized the GPU’s firmware so you are limited to the boards which have the custom firmware or use some code to bypass the custom firmware.

The NVIDIA GeForce GTX 980M is a larger MXM board Mobile PCI Express Module Electromechanical Specification which technically the system was not designed to support. The heat sink and cooler won’t fit properly.

Now here is where things get tricky! The code GamerTechX is pushing was developed with the assumption you are using the original CPU Apple was using so if you alter that you may break things.

You’ll note the CPU’s I commented on which don’t offer onboard graphics is also tied into this. Apple leverages the IG services for the startup command offerings. So things like diagnostics won’t work without the IG.

So the bottom line…

Pushing the RAM to 16 GB is likely the best option for most folks. Stick with the Intel Core i7-2600S CPU and realize this system has its limits for graphics. If you need more power then maybe its time to invest in a more powerful system.

While I want people to use their systems they already have to the max, just like a kid can out grow their clothes and shoes, we too can out grow our systems too!

Conceder passing your system to someone who could use it and getting either a used or new system which meets your needs!