Chosen Solution
On my iMac (27” Mid 2010) I would like to use it with a 1440p monitor, but whenever I connect it to the monitor, it will only support a maximum resolution of 1080p. I discovered the adapters I had tried to use, only supported a maximum resolution of 1080p, so I purchased this: https://www.amazon.com/gp/product/B010SD… which supports up to 4K. When it arrived, I tried using it with the iMac but still it only would support 1080p max, so I tested the adapter with a 2013 MacBook Pro, and oddly it worked at 1440p. Does anyone have suggestions to fix this strange issue?
Your systems graphics can’t push anything higher! “Apple reports that this model simultaneously supports the native resolution of the built-in display and up-to a 30-inch external display (2560x1600)”