As stated, the patent issues are keeping this out of the US for now, so the lack of a UL mark might have something to do with that. If/when that's resolved, then we can see if the UL is listed.

huh? yeah...

Heat goes faster through copper than through aluminum. But aluminum can dissipate the heat faster into the air. This is why we have today mostly aluminum-coolers with a copper base which Cooler Master used for these power supplies now...

We do regular comparisons with the Buyer's Guide and sometimes in roundups.

For starters your mentioned unit comes from Acbel and is not even half as tough as an Enhance-build PSU like the Silentpro.

I don't believe that aluminum dissipates heat faster than copper does. The reason why we have heatsinks that are a mix is probably because aluminum is much cheaper (and lighter, though that is probably a secondary rather than primary factor).

I agree. I think we need mythbusters on this one. Cu has higher conductivity than Al. But, Cu is heavier, more expensive and harder to machine so we reach the compromise of Cu base and Al fins.

It's true Cu retains heat better than Al.
Here are the simple clues:
Cu have higher conductivity and Specific heat than Al.
Conduction (CPU/Transistor to heatsink) needs good thermal conductivity.
Convection (Heat sink's fins to ambient air) needs a lot of surface area.

simple explaination:
While with higher conductivity, Cu will transport heat faster, but with the higher spec. heat Cu will stores more energy than Al (at the same shape and volume) while having the same surface area, thus Cu will be harder to dissipate convectively.

Now the long explaination:
Copper is a good candidate as first line 'heat sink', it will absorb a lot of energy before increasing 1 deg, meaning for a CPU at 47 deg and ambient at 27 deg, it will hold 27... 28... 29... 30 deg longer than Al as it heats up. - GOOD

now comes the drawback, with the high specific heat, when copper try to release heat to ambient air, it will maintain it's hot temperature longer than Aluminum simply because it has to dissipate more energy to ambient air before dropping 1 deg in temp.
So, let's imagine copper fins with the same shape and volume as Al, it will take a lot more air to cool the copper (not to mention it's heavier too) than the Al. - BAD

Thus the reason using Al for fins, and copper for heat block (sink).
asborbing heat from transistor or CPU got to do with small contact surface area, in which case higher thermal conductivity allows lower interface junction temp). while the Al fins dissipate heat more efficiently (in terms of heat flux/weight/size) than cooper.

Now, heat sink is just like any other overclocking quest, you're bound by the weakest link. Thus to come up with a good heatsink assembly you need to have properly sized Cu sink & Al fin.
This means sufficient surface area between the Al & Cu interface to sustain the same heat flux rate that the Cu is capable to aborb and Al fins capable to dissipate.
Mess this balance up, and your again bound by your weakest link, be it your copper block, Al fins of its Cu-Al interface area.

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