Replacing PSU fans

[Sheep221]

Hi I have couple of old but good PSUs lying around, that are fine except the fans just are way too loud and cleaning+adding some extra grease doesn't help at all.
I could possibly buy a new ones but still new PSU will also come to this after a few years, the electronics will remain ok while fan goes nuts.
If I would get decent silent after market fans and install them, would it be working well with their heat-RPM regulation? Would it be safe at all in terms of cooling?

 

[Yuriman]

I've swapped fans before in power supplies. As long as you're not pushing them too hard, a slightly slower / quieter fan could be better. However, it's not uncommon to find new, quality units (FSP, Antec Green) for $25 and under, often with free shipping, so I only generally bother with fan swaps if I have both PSU and fan lying around.