iMac mid-2007 as external display...

[mmm2509]

I recently purchased the iMac (Retina 4K, 21.5-inch, 2019) to replace my mid-2007 iMac. I thought it would be easy to use it as an external display, but after buying the proper adapters I see it is not so simple. One item I just read is how my 2007 iMac only has a video out port, which is obvioulsy why the adapters didn't work. Is this the end of the road? Is there really no way to use this huge 24 inch computer screen as a second display?

Much thanks

 

[Juicy Box]

You are probably thinking of Target Display Mode, what was only supported on the Late 2009 - Mid 2010 27" iMacs, the Mid 2011 to Late 2013 21" or 27" iMacs, and the Mid 2014 21" iMacs.

Your Mid 2007 iMac is not supported.

I think the only way to use your Mid-2007 as a display is to used a USB video input device which should work, but will also have latency involved and probably not be ideal depending on what you are wanting to do.

 

[chscag]

There used to be a program called "ScreenRecycler" which allows using the screen of a Mac as a second monitor. Their site is no longer up. If you can find a copy of that program it will work. And yes, it does work with iMacs that only have a video output connection.

 

[pepperonibois]

I've done some research to do the same for the 24" iMacs I have laying around. Long story short, it involves some hacking and more money than it's worth imo.

Essentially if you want to use an old iMac as a monitor, you need to gut the case and install an aftermarket display board and backlight driver. It's not too difficult if you have some electronics or repair experience, but definitely not a beginner project.

A lot of resources exist for the 17" and 20" models since the parts are cheap and plentiful on eBay, but the 24" models are a different beast because of their uncommon 1920x1200 resolution. I found a few display boards that were compatible with that panel, but they are expensive and not guaranteed to work without some modification. For the $300ish (and my time) that it would cost to do the project, it makes way more sense to scrap the old machine and buy a really nice modern QHD monitor instead.