Need to enable 1080p HIDPI on 2k monitor iMac

[NodeOfJS]

Hi everyone, I did a lot of research on web that my imac 2011 27" can enable 1080p HIDPI by terminal or switchResX, （I fellow this instruction https://comsysto.github.io/Display-...or-with-HiDPI-Support-For-Scaled-Resolutions/）I try to do all the method on Rumors and Github , and also disable the SIP, and I have replaced the plist file manually of my internal monitor, I can see the custom resolution ,but system （10.13.6 High Sierra）still can not provide 1080p HIDPI the max is 720p. Did I miss something?

 

[Fishrrman]

What is the make, model and native resolution of the monitor that you're using?
is it:
- 1080p? (1920x1080)
- 1440p? (2550x1440)

 

[NodeOfJS]

What is the make, model and native resolution of the monitor that you're using?
is it:
- 1080p? (1920x1080)
- 1440p? (2550x1440)

@Fishrrman

My model is 2011 mid iMac 27" A1312 (EMC 2429), the native resolution is 2550x 1440.

 

[Fishrrman]

In post 1 you wrote:
" my imac 2011 27" can enable 1080p HIDPI"

In post 3 you added:
"My model is 2011 mid iMac 27" A1312 (EMC 2429), the native resolution is 2550x 1440"

By 1080p HiDPI, do you really mean 4k that "looks like" 1080p?
Because to have a display running in HiDPI that looks like 1080p, you need to have a 4k display with a native resolution of 3840x2160.

Since the iMac you have has a native resolution of only 2550x1440 (1440p), you can't get a HiDPI image that looks like 1080p, because "the pixels aren't there"... literally.
SwitchRes can't display more pixels than what is physically there. All it can do is tinker with the possible resolutions available for the pixels that you have.

It looks like SwitchRes -can- give you an HiDPI image of 1280x720.
But that's "the most you're gonna get" from that display panel.

 

[NodeOfJS]

In post 1 you wrote:
" my imac 2011 27" can enable 1080p HIDPI"

In post 3 you added:
"My model is 2011 mid iMac 27" A1312 (EMC 2429), the native resolution is 2550x 1440"

By 1080p HiDPI, do you really mean 4k that "looks like" 1080p?
Because to have a display running in HiDPI that looks like 1080p, you need to have a 4k display with a native resolution of 3840x2160.

Since the iMac you have has a native resolution of only 2550x1440 (1440p), you can't get a HiDPI image that looks like 1080p, because "the pixels aren't there"... literally.
SwitchRes can't display more pixels than what is physically there. All it can do is tinker with the possible resolutions available for the pixels that you have.

It looks like SwitchRes -can- give you an HiDPI image of 1280x720.
But that's "the most you're gonna get" from that display panel.

Hi, many ppl have done with same model of my iMac it is the way force OS to give me HIDPI, the main idea is trick OS that I have the HIGH resolution monitor. I think this method is not available in 10.13.6.

 

[Fishrrman]

You can't coax a display to give you a resolution that is greater than the number of physical pixels that the display has.

Provide a link that describes how "many ppl" have done this?