Noctua NH-D15, Premium CPU Cooler with 2x NF-A15 PWM 140mm Fans (AWARD WINNING) NF-A15-PWM Built on the basis of the legendary NH-D14 and carrying on its quest for ultimate quiet cooling performance, Noctua’s flagship model NH-D15 is an elite-class dual tower cooler for the highest demands. Its expanded heatpipe layout and two premium grade NF-A15 140mm fans with PWM support for automatic speed control allow it to further improve the NH-D14’s award-winning efficiency. Topped off with the trusted, pro-grade SecuFirm2™ multi-socket mounting system, Noctua’s proven NT-H1 thermal compound , the NH-D15 forms a complete premium quality solution that represents a deluxe choice for overclockers and silent-enthusiasts alike. Details Based on the award-winning NH-D14 Noctua’s NH-D14 has received more than 350 awards and recommendations from leading international hardware websites and magazines, making it one of the most successful premium heatsinks ever built. With its expanded layout and dual NF-A15 fans, the NH-D15 further improves the D14’s much acclaimed quiet cooling performance. 6 heatpipe dual tower design As compared to conventional single tower heatinks, the NH-D15’s fine-tuned six heatpipe dual tower design provides more surface area, better heat-distribution and superior airflow efficiency in dual fan mode. Widened fin stack and expanded heatpipe layout Compared to the NH-D14, the NH-D15’s fin-stack has been widened from 140 to 150mm and its heatpipes are now spaced further apart, which allows for a more uniform heat distribution over a larger surface area and thus contributes to the NH-D15’s superior efficiency. High RAM compatibility in single fan mode Thanks to its recessed lower fins, the NH-D15 provides 66mm clearance for tall memory heatsinks in single fan mode, making it compatible with most high end RAM modules on the market. In dual fan mode, the NH-D15 should be used with standard height RAM (up to 32mm