Thermally conductive tape, any good for hs additional cooling?

Saw a system with a standard Taisol cooler, but there was a 2cm wide tape connected btwn the HS and the PSU holder, later figured it was a copper or like thermally conductive tape. This was a factory installed thing. As PSUs usually have powerful air cooling I figured this was not so bad idea. I do not have means to test this out, so I was wondering how much cooler this can make. For many of us even a 2degrees C reduction in temp would mean something. Any other methods(ie to replace the tape as that is not available in every shop) of leading the temp off the HS except a fan? thanks.

A friends M7VKA pushes out 1,82Vcore and makes the Morgan very hot, & space is limited for a good cooler.