Hooking up an external monitor

[frostygirl]

Hi all,
I have a 21.5 iMac running Mojave. I am trying to hook up an external monitor to this iMac. It's an ASUS monitor, probably 6 years old or so.
I have tried a HDMI cable to a USB-c. I then went into display. Hit the option key to "Detect" and nothing is found. So then I bought a VGA adapter to USB-C and still nothing. Could it be the monitor is too old? I can't believe I'm having so much trouble trying to set up an external monitor. Any suggestions? Thank you

 

[pigoo3]

Hey there frostygirl thanks for stopping by.

Please verify for us the following:

- Exactly what model iMac it is (there are lots of 21.5" iMac's).
- What ports does the Asus monitor have.

Knowing this info...we can suggest what adapters and/or cables you will need.

HTH,

- Nick

p.s. Normally you should only need to plug everything in...and all should work. Have you tried rebooting the computer after connecting everything?

 

[frostygirl]

Hi, its a 21.5 , 2107 iMac Retina 4K, 3 Ghz Intel core I5,Memory 8 GB 2400 Mhz DDR4, Graphis Radeon Pro 555 2 GB, 1 TB HD. The Asus monitor picture and the iMac picture is attached. Thank you

 

[Slydude]

This should be pretty easy. I've connected monitors older than that to iMacs. If I had to choose I'd choose DVI over VGA. A cable such as the one should get the job done. It's a Thunderbolt to DVI cable. Some manufacturers refer to this as a Mini DisplayPort cable.

 

[pm-r]

Hi, its a 21.5 , 2107 iMac Retina 4K,...

Hmmm..., maybe that 2107 iMac is just too far advanced!!!

On a serious note, does the ASUS monitor have an option to choose and select what input Port is being used with what looks like a DVI connector connected???



- Patrick
======

 

[frostygirl]

sorry about the typo. the Asus monitor does have an option. I choose VGA when I try it with the VGA plug and HDMI with the HDMI plug. Those are the only two ones I have. I also purchased these (attached). Did I need to purchase a DVI adapter or just get a whole new monitor? Thanks

 

[pigoo3]

Personally I would stay away from VGA...I would try DVI before giving up.

- Nick

p.s. You didn't verify if you tried rebooting the computer after hooking everything up.

 

[pm-r]

Maybe have a look at some of the google hits here and you may want to modify the search for the particular Model:
Asus monitor inputs Mac - Google Search

Asus monitor inputs - Google Search

it seems that a restart of the monitor maybe needed as I glanced through the hits.

EDIT:
And how about this:

Switch ASUS Monitor Input from HDMI to DVI
Tags: hardware, monitor, asus

Tuesday, June 28, 2016 4:24:45 AM
Situation: We have an ASUS VS238 monitor that can can DVI, HDMI, and VGA inputs. We're wanting to switch from HDMI to either VGA or DVI input.

Problem: We unplugged the HDMI and plugged in the DVI cable and receive this message: HDMI No Signal.

Solution:

Turn off the monitor.
Turn the monitor on.
When "HDMI No Signal" appears, press the Input Select Button until you've switched to DVI.

Muddling Thru - Switch ASUS Monitor Input from HDMI to DVI

Hmmm... a press and hold trick to get the switch to take.it looks like. That's sneaky.



- Patrick
======

 

[frostygirl]

Thank you all for your suggestions. I have narrowed it down. The USB-c ports on my I-mac are not working. So its at the Apple Store now being repaired (new logic board). Thanks again.

 

[chscag]

Thanks for posting back and letting us know. Hopefully, Apple is repairing it for free.