Noctua NH-L9i Low Profile Heatsink Review

What's Inside


Installing the cooler is peanuts.  Apply a rice-grain-sized glob of the included thermal paste on the center of the CPU (I’m not going into discussion on how to apply TIM as everyone seem to have their own idea or preference to it, this method works for me just fine).

Align the holes of the cooler to the motherboard and screw in the thumb screws in a cross pattern tightening it  slowly (a bit like a car’s rim).  A normal Phillips screwdriver can be used, but don’t over-tighten or you might  destroy the thread on the cooler.  They should be nice and snug when tighened with fingers.


Plug in the fan cable in the CPU FAN outlet of your motherboard and you’re done!


I removed my big Noctua NH-D14 cooler and cleaned the CPU and the cooler base with some denatured alcohol KET  96% to remove any grease or old TIM before fitting the NH-L9i.  Turbo mode was disabled in the motherboard BIOS to let the CPU run at stock speed.

I switched on the PC and took a quick look at the temperatures, then left it running to warm up and settle in.  This comprised of me browsing the web and watching stuff on YouTube.

Testing the L9i meant using 100% fan speed in my case to get maximum ventilation as recommended.  I was probably just fine with standard speed but wanted to get the best out of it as I was running a higher wattage CPU than recommended.

NH-L9i idle (42 C) vs Load (64 C)

For temperatures I used Core Temp to give be a better idea on what it’s doing per core. For a quick graph I used the load tests I used Speccy, for load testing I let the pc run Prime95 In-place large FFT`s Torture test  for a minimum of 30 minutes using for maximum heat and power consumption.

I recorded a temperature of 42°C idle just letting the PC sit for 10 minutes with full case ventilation.

After about 50 minutes I managed to score a temperature of 64°C.

Needless to say I was well impressed with this score taking into account that it really is just a flipping small cooler.