Optimus, EK Magnitude and TechN all get just a bit better than the HKIV pro. They were top dog for awhile. Ive only test Intel versions on HEDT and was running a HKIV pro before newer blocks came out. TechN I just cant get past the look, ugly IMO and I dont like the rough cold plate but they do perform well. The 3 I mentioned are all competitive on a 10980XE. I can call a clear winner as there just wasnt any AHA moment. They all did achieve 3C lower than the HK in Heavy AVX workloads as is out of the box random production samples. Right now Im running the EK Magnitude with a flat cold plate that isnt quite flat and it gets me another 1-2C improvement as did the Optimus Signature V2 with the internal Oring removed reducing the bow. I have an Optimus block I purchased as a Blem with the block itself made for a flatter profile. Im about to give that one a run and see what I get as Im about to tear into my rig AGAIN...putting the GPUs back horizontal to gain access to the buttons on the lower left of my MOBO that are pretty important as well as open up so PCIE slots as the vertical mount blocks all of them. Also going to use one empty slot for my in and out of a MORA3 420 and install the Intel 960GB 905P AIC I just scored that's got all of 8 hours on it for half of retail. Ive been busy as hell with work but I have to get this 905P in and tested out before my 30 day return window closes. Ive had the MORA 3 ready to go for a couple of months now but work went from hardly anything to do to 60 hours being a short week. 76 hours this week. Guess Im gonna have to burn up some PTO days to get it done. Only used 3 days out of my 6 weeks so I have a lot to burn. Probably take off the entire month of July.