tymimeagain wrote:
I'm having a little difficulty following what you're saying, but I will say that with the monitor and cable I'm using, I only have these resolutions to choose from:
…
None of them say "Retina" or "UI looks like", so I'm not at all sure which one would be an equivalent to what you recommend, if any.
All of the resolutions in the list are "UI looks like" resolutions. One of them (3840 x 2160) also happens to be the native resolution of your monitor's LCD panel. The phrase "UI looks like" is one that I picked up from the System Information (Option- > System Information…) application.
If you look at the list, you'll see there's only one entry for 3840 x 2160 – and I think that's because the monitor has told the Mac that this is its native resolution. Many of the others have two entries, e.g.,
- 2560 x 1440
- 2560 x 1440 (low resolution)
or
- 1920 x 1080 (low resolution)
- 1920 x 1080 (Default)
The ones that say "(low resolution)" aren't Retina modes. You select 1920 x 1080 (low resolution) or 2560 x 1440 (low resolution) and the Mac will generate a signal with that lower resolution, and the monitor will scale it up (using the equivalent of digital zoom), and you may not like the results too much.
The other ones that are "lower resolution" than your monitor, but that don't say "(low resolution)" by them, are the Retina modes, where the Mac will draw on a canvas with 2x as many pixels in each direction.
Here's an example. I have a different Dell 4K monitor. In System Settings > Displays, I selected the icon next to Larger Text. It corresponds to Retina "UI looks like 2560 x 1440" mode. If I "Show resolutions as list" and "Show all resolutions", the selection comes up as "2560 x 1440".
In System Information, I see:
The monitor tells me it is receiving a 3840 x 2160 signal.
