Continuing the renowned legacy of Noctua''s award-winning NH-U9 series, the NH-U9S is a premium quality quiet CPU cooler in classic 9cm size. Its asymmetrical design with 5 heatpipes not only provides even better cooling performance than the previous generation but also improves compatibility: Thanks to its 95x95mm footprint, the NH-U9S clears the RAM and PCIe slots on all Intel and most AMD based mainboards, including µATX and ITX. Combined with its 125mm height, this makes the NH-U9S a highly versatile solution with excellent case, RAM and PCIe compatibility. The included NF-A9 premium fan supports automatic speed control via PWM for outstanding quietness of operation and a second, optional NF-A9 fan can be added for further improved performance in dual fan mode. Topped off with the trusted, pro-grade SecuFirm2™ multi-socket mounting system, Noctua''s proven NT-H1 thermal compound and full 6 years manufacturer''s warranty, the NH-U9S is a deluxe choice through and through.Details Award-winning NH-U series The NH-U9S stems from Noctua''s award-winning NH-U9 series. First introduced in 2005, the NH-U series has become a standard choice for premium quality quiet CPU coolers and won more than 800 awards and recommendations from leading international hardware websites and magazines. S version with better compatibility Like its bigger brothers NH-U12S and NH-U14S, the NH-U9S features a revised, slimmer layout: Whereas the NH-U9B SE2 was 120mm deep with its two stock fans, the NH-U9S is asymmetrically built and measures only 95mm with its single, more efficient NF-A9 fan, thus providing better performance and compatibility at the same time. 100% RAM compatibility With its 95x95mm footprint, the NH-U9S does not overhang the RAM slots on current Intel and most AMD mainboards. This gives the user full access to the memory modules and guarantees 100% compatibility with tall heatspreaders or optional memory fans.* 100% compatibility with PCIe cards on mini-ITX Many Intel LGA115x based mini-ITX motherboards have the PCIe slot sitting right next to the 95x95mm socket zone. While larger coolers that exceed this zone are likely to block the PCIe slot, the 95x95xmm sized NH-U9S provides full compatibility with PCIe cards, be it on ATX, microATX or ITX. NF-A9 premium fan The highly optimised features Noctua''s proprietary AAO frame as well as sophisticated aerodynamic design measures such as Flow Acceleration Channels, which allows it to further improve the renowned efficiency of Noctua''s previous 92mm models and contributes to the NH-U9S'' superior cooling performance. PWM support and Low-Noise Adaptor The NF-A9 92mm fan supplied with the NH-U9S supports PWM for convenient automatic speed control through the motherboard. In addition, the maximum fan speed can be reduced from 2000 to 1550rpm using the supplied Low-Noise Adaptor for even quieter operation. Dual fan ready The NH-U9S includes an extra set of fan mounting clips for users who want to achieve even better cooling performance by adding a second, optional NF-A9 PWM fan in order to create a push/pull setup. Using the y-cable supplied with the NF-A9 PWM retail fan, both fans can be connected to one CPU fan header.