
The Noctua NH-D15S comes with only one fan, so i am curious to how it will perform compared to my current Zalman CPNS9900-A LED CPU cooler on my 4790K @ 4.4 Ghz: i get 74° C on the CPU (= the lid), the cores well over the 80's ° C on the hottest core, in the Everest stress test, at 22° C room temperature.
EDIT: it is overall 0.5 to 1 degree celsius cooler during the everest stress test. I call this room temperature fluctuation. I am not convinced there is a significant difference. I would say they perform the same.
The Zalman has a very efficient airflow as it blows freely through a hole in the circle of copper.
The Noctua (i have only one fan installed between the 2 metal towers) is blowing & sucking through two large metal grilles. It has maybe 4 times more metal cooling surface than the Zalman.
Both are top notch, powerful and effective.
The Noctua is quieter!