Tt 6CU is good, Tt 6CU+ (7200 RPM) is much louder and only about 1 degree C better in cooling. I just changed out a 6CU+ for a Swiftech MCX642 and dropped my temperatures 6-7 degrees C under full load! The Swifty is just plain AWESOME! (of course at 4x the price!) It is even quieter that the 6CU+ because the fan is ONLY 5000 RPM and produces a lower pitch noise, though still quite loud. My Athlon C 1.4 GHZ is now game stable at 1.6 GHZ and 39-40 degrees C.
Current Main Rig:
AMD FX55 @ 2.9 GHz
2 GB PC 3200 DDR RAM
ABIT KN8 SLi motherboard
ATI X1900XT O/C to XTX speeds
They have another all copper one with a delta fan that performs OK (the HHC-002). The rest are very very very bad.
The Volcano 6Cu is a well designed basic heatsink with a nice copper insert, good quality manufacturing, and a respectable, but not too loud fan on it. The perfromance is not the best, but it perfroms MUCH better than all the other CoolerMaster heatsinks and would probably give even the HHC-002 a good run. It is also very cheap.
A heat spreader helps the performance quite a bit, but is not necisary. I use a GlobalWin FOP32-1. It is an older, but very good all aluminum heatsink . It is a very good design and is actually smaller that the V-6Cu, but uses a similar fan. It works great on my Duron 600@900Mhz. I use Acrtic Silver II for thermal compound between the CPU and heatsink. I run about 36'C full load. My main system has an AthlonXP 1600+ and it too has a FOP32-1, but I spread the fins out a bit so it would fit a larger 80mm fan. The fan generate about 30% more air for about 1/4 the noise. This thing is wisper quiet. I do not know if it performs any better, just quieter. I run about 42'C full load with this system. I am thinking of getting a V-6Cu also. As I said it is a bit bigger than the FOP32-1 (60x80 instead of 60x72) and the copper heatspreader will help too. After mod'n it will be 80x80mm and I will add a nice low RPM fan onto it, but likely a little better than the one I use now. I should have now problem getting below 40'C with this.
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