My Noctua U12A heatsink does not get hot while running Cinebench 20, it's just feels warm, but the hottest core on my CPU hits 90C within 20 seconds while the heatsink is just warm at that point. I heard that if the heatsink does not feel hot that means that there is poor contact with the CPU and heatsink and therefore heat dissipation is poor. My 5800x at 90C in Cinebench 20 maintains 4.4-4.5 GHz and the resulting score is around 6000. I did try PBO with Curve Optimizer set to -20 offset for all-core but regardless, it still hits 90C within 20 seconds, only it runs a little faster. I right now have $20 worth of BB gift cards and the H100i iCUE AIO is on sale for $140 at BB and the H150i iCUE is on sale for $168 at BB. I have a Meshify C case with the 2 stock fans as intakes and a CoolerMaster Silent 120mm as rear exhaust. Am I better off buying the H100i iCUE and top mounting the radiator and setting it's fans as exhaust or am I better off buying the H150i iCUE and front mounting the radiator and setting it's fans as intake? I also have a GTX 1080 Ti that reaches 84C in the Unigine Heaven benchmark within a minute, so I don't want my GPU temperature to get hotter or throttle more if I decide to get a 360mm AIO and front mount it.