Quote Originally Posted by Dani
BigTyphoon is the suckiest cooler for subzero temps like all heatpipe coolers are..
I tried my Opt 146 last winter with -10'C ambient temp, liquid in pipes frozed = CPU temps around +50'C
Best temp for TT BigTyphoon is -2'C..

Best cooler (no heatpipes) for real low subzero ambient temp is ZM7700 with 120mm Delta EHE

Indeed, the Big Typhoon (all heatpipes coolers for that matters) are not the best coolers for subzero temps.
I'am busy with creating a home made cooler from aluminium.
Hopefully that will work for subzero temps.