From most manufacturers, when a new product comes out we can expect to see a notable change to the predecessors. For one particular vendor, though, that's not always the case. We're talking about Noctua, of course. Today, the Austria-based cooling company announced two new coolers, the NH-C14S and the NH-D15S. Both of these are single-fan successors to their older counterparts.

The NH-C14S is a C-type cooler that succeeds the NH-C14, and in order to make up for having just a single fan, it has a deeper fin stack. According to Noctua, it therefore cools similarly to the NH-C14, while increasing flexibility. You'll be able to mount the fan at the top of the cooler, giving you increased RAM clearance, or underneath the fin stack for a lower total height, increasing compatibility with narrower enclosures.

The cooler ships with the NF-A14 PWM fan, which can spin at speeds up to 1500 RPM and has an acoustic footprint of 24.6 dBA. A low-noise adapter brings those numbers down to 1200 RPM and 19.2 dBA. Thanks to its PWM support, you can bring its speed down as low as 300 RPM, where it will be pretty much inaudible yet still offer enough cooling performance for an idling CPU.

The NH-D15S stems from the NH-D15, but again, it comes with just a single NF-A15 PWM fan. The dual-tower fin stack design is shaped so that it clears the top PCI-Express port and leaves 65 mm clearance for RAM modules.

The NF-A15 PWM fan included is a little different from the retail version. This one spins at up to 1500 RPM instead of just 1200 RPM. Therefore, it has the same performance characteristics as the NF-A14 PWM fan, because the only difference between the A15 fan and the A14 fan is the frame -- the impeller and motor are the same. Optionally, you'll be able to add a 120 mm fan, or a 140 mm fan housed in a round frame with 120 mm mounting points.

Both of the coolers come with Noctua's excellent SecuFirm2 mounting system. They are also compatible with all mainstream CPU sockets from both Intel and AMD.

The NH-C14S will be available any moment now for $74.90, while the NH-D15S will take a couple weeks longer, landing in June for $79.90.

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