Using an old imac as a monitor

[rlyacht]

I have a mid-2007 imac that I'd like to use as an external monitor for a laptop. The imac has a mini-dvi port, so at least in terms of connections, I'd need a mini-dvi to hdmi. Such things exists (e.g. at Monoprice) but will it work? As I understand it, the mini-dvi port was intended to allow the imac to output to an external monitor, not to be used as one.

Any advice appreciated ...

 

[DeltaMac]

You understand correctly. Your old iMac has a miniDVI port, which is for output to an external display.
There is no video input before iMacs came with mini DisplayPort, and the Late 2009 27-inch was the first with Target Display mode, and nearly 2 years before the 21.5-inch iMac had that mode.
So, you can't connect the iMac directly, and the only other option would be to use that on a network/screen sharing, which would not be same experience as a direct connection.

 

[rlyacht]

Thanks, too bad .. it's still a nice big monitor. I'll see if I can use some lightweight screen sharing thing.