Noctua NH-L9I review

After all the huge tower fans we've looked at recently, it makes a refreshing change to be playing with something at the other end of the spectrum. Noctua's NH-L9i is a compact top cooler - and when we say compact, we mean it.

The NH-L9i is a mere 37mm high and weighs just 420g. With a footprint of just 95 x 95mm, it's made for smaller motherboards with limited space around the CPU socket. To give you an idea of just how compact the cooler itself is, 14mm of its 37mm height is taken up by the cooling fan.

This is the Intel version, and as such only supports Intel's Socket LGA1155 and LGA 1156 series of CPUs. If you want a compact cooler for an AMD chip, you need the NH-L9a, which supports AM3+/FM1 as well as FM2 sockets. The only real difference is the clipping mechanism.

Fit for purpose

Fitting the Noctua NH-L9i is a doddle and, amazingly, it takes longer to describe than to do. That said, you still have to mount it on the mobo before you build the system if your chassis doesn't have a large cutout in the motherboard plate. The four screws used by the mounting (which the company calls the SecuFirm2) are tightened to the rear of the board. Yep, that's it - just four screws.

Noctua has made the heads of these big enough for you to use your fingers for the initial tightening, before resorting to a screwdriver.

With a cooler this small there's no worry about obstructing any of your DIMM slots, so you're free to use any memory you fancy - including those with the most outlandish of heat sinks.

Also bundled in the box is a set of longer screws that enable the fitting of one of Noctua's 92 x 25mm fans if there's enough room in the case. That would give a bit more cooling performance compared with the 92 x 14mm version supplied as standard. Noctua also backs it with an impressive six-year warranty.

The NH-L9i uses a nickel-plated copper contact plate and dual U-shaped heatpipes. These heatpipes then run through a multi-finned aluminium array, giving it some impressive cooling chops. Noctua recommends that the NH-L9i is used with a CPU with a TDP of 65W or less.

Unfortunately our test rig uses an i7-3770K, which has a TDP of 77W. It was therefore a little out of its comfort zone when tested, but at stock speeds it coped well both when the CPU was idling and at 100 per cent - especially given the size of its cooling fan. Even at 100 per cent it was comfortably under the 105°C TJ Max temp of the i7-3770K.

Benchmarks

Idle CPU performance
3770K @ 3.5GHz: Degrees centigrade: Lower is better
NOCTUA NH-L9I: 35
THERMALRIGHT AXP-100: 35
COOLER MASTER BLIZARD T2: 25

100% CPU performance
3770K @ 3.5GHz: Degrees centigrade: Lower is better
NOCTUA NH-L9I: 76
THERMALRIGHT AXP-100: 68
COOLER MASTER BLIZARD T2: 73

Peak to idle performance
3770K @ 3.5GHz: Seconds: Faster is better
NOCTUA NH-L9I: 145
THERMALRIGHT AXP-100: 86
COOLER MASTER BLIZARD T2: 172

Noctua also says the cooler isn't recommended for overclocking, but we gave it a shot anyway. At idle it kept the 3770K running at 4.5GHz reasonably cool but running the CPU at 100 per cent it was a completely different story as the core temperature soared past the TJ Max temp in under minute, so we stopped the test to save our blushes.

The cooler is designed with a mini-ITX mobo/compact HTPC scenario in mind, so an i7 is overkill anyway. Put this cooler on a low wattage i5 or i3 and it will keep the CPU cool in a small form factor case, and do it quietly - just what you need in an HTPC.