iMac 27 Late 2012 randomly shuts down while using
I have a very old iMac that still runs well but for the last 2 years it keeps powering down for no reason.
I had done research and I worked out it was likely the power supply so I changed the cable and that worked for about a year, but now it has started doing the same again.
I can get it to turn back on by fiddling with the fuse in the power cable but this only lasts for an hour or so - depending on what application I’m using - before it just shuts down again.
After further research, it sounds as if the issue may be to do with the actual power supply **board**.
Does anyone know much might it cost to repair/replace something like this? I've been pretty happy with this machine and don't want to have to shell out for a new one at a similar spec. If a repair is cheap enough, I'll do that instead.
Thanks for any help in advance!
iMac 27″, macOS 10.13