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I bought my 4,1 the minute the apple store opened back in March, 2009. I've probably put as much money into it as I paid for it ($2,499). I agree that this is probably the last-hurrah for this model. It's not very apple-like to support a 10 year old computer with their most modern features. I sense a little guilt over the trashcan... That said, the new "modular" (whatever that will mean) MacPro will probably mean no more OS updates for the 4-5,1's.

But from my standpoint, it'll only be obsolete once the apps I need to run, can't run anymore. It'll be a slow painful death as one by one I have to figure out work arounds. But I think that's a few years away yet.

Oh... and 10.13.4 seems to work just fine for me.
 
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