Noctua’s passive cooler can silently handle an Intel Core i9-11900K – but don't overclock it

Noctua NH-P1
(Image credit: Noctua)

Noctua has launched a passive CPU cooler, meaning one that dispenses with the need for any fan and therefore works completely silently – and it can tackle Intel’s Rocket Lake flagship processor (although as you might expect, this comes with a bunch of caveats).

First off, let’s look at the cooler itself, the Noctua NH-P1 which the manufacturer promises has been designed from scratch to work without the need for a fan bolted to it.

Noctua’s chief executive, Roland Mossig, explains: “The NH-P1 is our very first passive cooler, and it should be easy to see that we didn’t just take a regular heatsink and omit the fan. A lot of engineering work went into designing this unit for fanless operation from the ground up and we’re truly proud of the end result.”

The result being that it can cope with taming Intel’s Core i9-11900K processor, albeit running at its stock speed – but that’s still impressive for totally silent operation. In Noctua’s testing, the 11900K ran at around 3.6GHz (1,00MHz faster than the stock clock, in fact), and that’s being stress-tested with Prime 95.

Noctua NH-P1

(Image credit: Noctua)

However, under the list of the fan’s compatible processors, Noctua does note that the 11900K (and indeed other high-end models) might “fall slightly below base-clock under continuous full load”.

In other words, don’t expect too much pep from beefy chips – and it goes without saying, don’t even think about overclocking with this cooler.

In fact, you need to step down to the Core i5-11600 for Noctua to remove the potential thermal throttling warning for fanless operation, or the Ryzen 5 3600 on the AMD front.

Cooler compromise

For those who do want to get a better level of performance out of the CPU, Noctua offers an option to attach a 120mm fan (NF-A12x25 LS-PWM). But, doesn’t that defeat the whole point of the silent exercise?

Well, sort of, but the thing is this add-on fan is a low-speed and “ultra-quiet” model, so you won’t be hearing much noise from it – a rated 12.1dB at most – and it can be set as semi-passive. That means it only kicks in when the PC needs it, leaving operation completely silent when you’re not doing anything particularly demanding.

Noctua goes to pains to make it clear that anyone wanting to use the NH-P1 in passive mode to make a silent system should be aware that there are lots of considerations in designing such a stealth PC (maybe as a living room HTPC).

You’ll need a well-designed roomy PC case with good airflow – Noctua recommends a bunch of those here – and careful selection of accompanying components aside from the CPU plus cooler. The vendor offers a load of advice on considerations to take into account here, plus there’s a how to video on YouTube too.

The NH-P1 is out now (though it’s still not yet in stock on Amazon at the time of writing) and retails at $110 (around £78, AU$143), with the optional NF-A12x25 LS-PWM fan costing $30 (around £21, AU$39).

Via VideoCardz

Darren is a freelancer writing news and features for TechRadar (and occasionally T3) across a broad range of computing topics including CPUs, GPUs, various other hardware, VPNs, antivirus and more. He has written about tech for the best part of three decades, and writes books in his spare time (his debut novel - 'I Know What You Did Last Supper' - was published by Hachette UK in 2013).