Some claim old computers should be replaced with modern computers because modern processors have far lower idle wattages. A mid-range Intel Core2Duo 6400 from the 2008 era idles at 22w. Compare that to modern processors like my mid-range Ryzen 3600 at 21w.
A better argument for replacing older PCs is the last decade of lowering prices for 80% gold and higher efficiency power supplies that can actually delivery this efficiency at idle loads.
But any efficient modern power supply should be able to power an older computer too so this doesn't change much.
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