Hi all,
I thought I would post here rather than hijack the main '2011 iMac Graphics Card Upgrade' thread.
I have a 27" 2010 iMac, and just installed a K2100M 2GB. Flashing went fine using @Nick [D]vB's rom, the GPU is recognised as a K2100M by Nick DvB, and I installed OpenCore according to @herrdude's instructions here. However, something isn't working quite right. I have re-done the OpenCore installation twice following the instructions, but the below issues persist.
I am able to boot through OpenCore, but most of the time (not every time) I get a screen at boot saying 'Error: Already started returned from Opencore.efi", after which I am greeted with the OpenCore selection where I must click "Boot macOS from Macintosh SSD". After that I can boot fine into the MacOS, and adjust the brightness, which shows OpenCore is at least partly functional.
However, I also have issues with Target Display Mode. It works and I am able to use the iMac as an external monitor for my work PC through a USB-C->MdP cable as I have been for the last few months. However, I am unable to switch back out of TDM using Cmd+F2; the only way to return to the iMac is by unplugging the display cable. In addition, on TDM I no longer get sound to the iMac speakers. This used to work before the GPU replacement.
Does anyone how I can fix these issues? None of these are very serious, but are quite annoying! Thanks in advance!
PS: while I'm here, I thought I would also ask this also. On HWMonitor, all the temps seem fine except 'Power Heatsink 1' which is usually aroudn 76-77C (170F). Is this something I should be concerned about?
I thought I would post here rather than hijack the main '2011 iMac Graphics Card Upgrade' thread.
I have a 27" 2010 iMac, and just installed a K2100M 2GB. Flashing went fine using @Nick [D]vB's rom, the GPU is recognised as a K2100M by Nick DvB, and I installed OpenCore according to @herrdude's instructions here. However, something isn't working quite right. I have re-done the OpenCore installation twice following the instructions, but the below issues persist.
I am able to boot through OpenCore, but most of the time (not every time) I get a screen at boot saying 'Error: Already started returned from Opencore.efi", after which I am greeted with the OpenCore selection where I must click "Boot macOS from Macintosh SSD". After that I can boot fine into the MacOS, and adjust the brightness, which shows OpenCore is at least partly functional.
However, I also have issues with Target Display Mode. It works and I am able to use the iMac as an external monitor for my work PC through a USB-C->MdP cable as I have been for the last few months. However, I am unable to switch back out of TDM using Cmd+F2; the only way to return to the iMac is by unplugging the display cable. In addition, on TDM I no longer get sound to the iMac speakers. This used to work before the GPU replacement.
Does anyone how I can fix these issues? None of these are very serious, but are quite annoying! Thanks in advance!
PS: while I'm here, I thought I would also ask this also. On HWMonitor, all the temps seem fine except 'Power Heatsink 1' which is usually aroudn 76-77C (170F). Is this something I should be concerned about?