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Owz600

macrumors newbie
Original poster
Jan 14, 2021
1
0
I’ve read a bunch of threads on various sites and haven’t been able to clarify whether the late 2009 iMac 27” displays can be used as an external display for an M1 Mac Mini or M1 MacBook Air.

Does anyone have any insight into this?

The iMac has a Mini DisplayPort that could be used. However I’m unsure what cables or adapters would be needed and whether TDM would function?

My 09 iMac runs a patched version of high Sierra and I have read that the patched version doesn’t have TDM that can work with Big Sur...

Wonder if anyone has some understanding of how to go about connecting the monitor to the source (either Mac Mini or MacBook Air). Thanks
 

Deccr

macrumors member
Nov 29, 2020
56
39
This looks the cable you would need to connect a Mac mini or MBA to the iMac:


I can’t say if it would work your patched version of High Sierra. IIRC someone had an issue previously and it wouldn’t work - probably worth a quick search of the forum?
 

Chris Newbold

macrumors member
Sep 22, 2014
43
2
This looks the cable you would need to connect a Mac mini or MBA to the iMac:


I can’t say if it would work your patched version of High Sierra. IIRC someone had an issue previously and it wouldn’t work - probably worth a quick search of the forum?

I had this issue and posted about it. Patched high Sierra 2009 iMac 27”. Eventually I realised it was the high Sierra (breaks target display mode I think??) but couldn’t downgrade the 2009, lost patience and sent the Mac mini back.
 
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citivolus

macrumors 65816
Sep 19, 2008
1,193
259
I'm happily using my Late 2009 iMac running High Sierra (not patched) in TDM mode with my M1 MacBook Air. Works perfectly with the Displaylink drivers installed on the MacBook, Dell D6000 Thunderbolt 3 dock, and this Mini DisplayPort to DisplayPort cable. Why is the OP running a patched version of High Sierra?
 

Chris Newbold

macrumors member
Sep 22, 2014
43
2
I'm happily using my Late 2009 iMac running High Sierra (not patched) in TDM mode with my M1 MacBook Air. Works perfectly with the Displaylink drivers installed on the MacBook, Dell D6000 Thunderbolt 3 dock, and this Mini DisplayPort to DisplayPort cable. Why is the OP running a patched version of High Sierra?

Sorry in my case I meant patched Catalina.
 

Deccr

macrumors member
Nov 29, 2020
56
39
Target display mode will not work with a 2012 iMac unfortunately. Any iMac which uses thunderbolt for TDM will not work with M1 Macs. Only older iMacs which use DisplayPort for TDM will work.
 
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