i had that idea for some time, for complete passive cooling of the psu. it came to my mind when i saw a test in the german c't of a silent pc (pentium 4 something), that had absolutely no fans, just large heatsinks and heatpipes. i thought this could be easily done, if the components that need to be cooled would be in the right place.. for example (maybe stupid, but anyway), the cpu on the back of the mainboard, so it would touch the case, and one could install a really large heatsink (like the high-end amplifiers have) on the outside of the case!
but for the psu, one could just unsolder the hot components (like in the psu water cooling article
) and put some cables inbetween so you can put them where it's best for cooling!! like in the example above, put a large heatsink on the outside of the case, and cool all the hot psu components with it.
i didnt try it, since my pc (and psu) is already silent enough (here some photos
) (and because i'll get a new case soon, would have to do everything again), but i think it's a good and cheap way to get a fan-less psu!
anyone tried this already? any thoughts?