My daughter has a 2011 27” iMac (base model) and it just cannot keep up with modern games. XCOM 2 for example was unplayable even at the lowest settings. I decided to try an upgrade to a GTX 880M and used this guide as baseline even tough it was for the 21.5” model.
The GTX 880M was purchased off of eBay and reportedly came from an Alienware Laptop.
Here is a comparison of it and the 6770M the iMac had before…
The upgrade went great! The 880M is longer than the 6770M but still fits, especially because we also replaced the HD with a SSD. The difference in playing games is amazing, most games auto-detected the new card and changed their settings to the highest settings. XCOM 2 runs perfectly at medium settings, which is comparable to my 2015 5K iMac.
This upgrade was hard, but really worth it!
To get the computer to boot the first time I needed to use Safe Mode by holding down the shift key as soon as I hear the start up chime.
Once booted into safe mode, installing the nvidia Web Drivers made the system work perfectly. I also installed the CUDA drivers, but thats not required.
Web Drivers: http://www.insanelymac.com/forum/topic/3...
CUDA Drivers: http://www.nvidia.com/object/mac-driver-...
The computer will run really hot after the upgrade because the card has a much higher TDP (35W vs 122W). To prevent overheating I used SMC Fan Control to set the fans to a minimum speed of 2200 rpm.
SMC Fan Control: https://www.eidac.de/
- Gaming performance is amazing.
- Can play games we couldn’t even launch before.
- nvidia provides a driver!!! :-)
- Requires nvidia driver (check for updates before OS updates)
- Loss Boot Screen and Brightness Controls
- Higher Fan Speeds = Louder Mac