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[nextpage title=”Introduction”]
The Noctua NH-L9i is a low-profile CPU cooler that is only 1.46” (37 mm) tall and uses a 92 mm PWM fan. Let’s test it!
The NH-L9i comes in a small cardboard box, as seen in Figure 1.
Figure 1: Package
Figure 2 shows the contents of the box: the cooler itself, a tube of thermal compound, manual, a power adapter, a case badge, and four screws. The accessories come nicely fitted in a foam layer.
Figure 2: Accessories
Figure 3 displays the Noctua NH-L9i.
Figure 3: The Noctua NH-L9i
This cooler is discussed in detail in the following pages.
[nextpage title=”The Noctua NH-L9i”]
Figure 4 illustrates the front of the cooler, where you can see how thin (0.9” or 23 mm) the heatsink is, and the fan (0.55” or 14 mm). You can also see the tips of the two heatpipes.
Figure 4: Front view
Figure 5 reveals the rear of the cooler.
Figure 5: Rear view
In Figure 6, you can see the side of the cooler.
Figure 6: Side view
Figure 7 shows the top of the cooler, completely covered by the 92 mm fan.
Figure 7: Top view
[nextpage title=”The Noctua NH-L9i (Cont’d)”]
Figure 8 illustrates the bottom of the cooler. The nickel-plated copper base is very well polished.
Figure 8: Bottom view
Figure 9 reveals the heatsink with the fan removed.
Figure 9: Heatsink
The 92 mm PWM fan that comes with the NH-L9i is shown in Figure 10. The cooler is also compatible with thicker (1” or 25 mm) 92 mm fans.
Figure 10: Fan
[nextpage title=”Installation”]
The installation of the Noctua NH-L9i is very simple. Just put the cooler over the CPU, insert and screw the four screws from the solder side of the motherboard, as shown in Figure 11.
Figure 11: Screws on the solder side
Figure 12 shows the NH-L9i installed in our computer.
Figure 12: Cooler installed
[nextpage title=”How We Tested”]
We tested the cooler with a Core i5-2500K CPU (quad-core, 3.3 GHz), which is a socket LGA1155 processor with a 95 W TDP (Thermal Design Power). In order to get higher thermal dissipation, we overclocked it to 4.0 GHz (100 MHz base clock and x40 multiplier), with 1.3 V core voltage (Vcore). This CPU was able to reach 4.8 GHz with its default core voltage, but at this setting, the processor enters thermal throttling when using mainstream coolers, reducing the clock and thus the thermal dissipation. This could interfere with the temperature readings, so we chose to maintain a moderate overclocking.
We measured noise and temperature with the CPU under full load. In order to get 100% CPU usage in all cores, we ran Prime 95 25.11 with the “In-place Large FFTs” option. (In this version, the software uses all available threads.)
We compared the tested cooler to other coolers we already tested, and to the stock cooler that comes with the Core i5-2500K CPU. Note that the results cannot be compared to measures taken on a different hardware configuration, so we retested some “old” coolers with this new methodology. This means you can find different values in older reviews than the values you will read on the next page. Every cooler was tested with the thermal compound that comes with it.
Room temperature measurements were taken with a digital thermometer. The core temperature was read with the SpeedFan program (available from the CPU thermal sensors), using an arithmetic average of the core temperature readings.
During the tests, the panels of the computer case were closed. The front and rear case fans were spinning at minimum speed in order to simulate the “normal” cooler use on a well-ventilated case. We assume that is the common setup used by a cooling enthusiast or overclocker.
The sound pressure level (SPL) was measured with a digital noise meter, with its sensor placed near the top opening of the case. This measurement is only for comparison purposes, because a precise SPL measurement needs to be made inside an acoustically insulated room with no other noise sources, which is not the case here.
Hardware Configuration
- Processor: Core i5-2500K
- Motherboard: ASUS Maximus IV Extreme-Z
- Memory: 6 GB OCZ (DDR3-1600/PC3-12800), configured at 1,600 MHz and 8-8-8-18 timings
- Hard disk: Seagate Barracuda XT 2 TB
- Video card: Point of View GeForce GTX 460 1 GB
- Video resolution: 1920×1080
- Video moni
tor: Samsung SyncMaster P2470HN - Power supply: Seventeam ST-550P-AM
- Case: Cooler Master HAF 922
Operating System Configuration
- Windows 7 Home Premium 64 bit SP1
Software Used
Error Margin
We adopted a 2°C error margin, meaning temperature differences below 2°C are considered irrelevant.
[nextpage title=”Our Tests”]
The table below presents the results of our measurements. We repeated the same test on all coolers listed below. Each measurement was taken with the CPU at full load. In the models with a fan supporting PWM, the motherboard controlled the fan speed according to core load and temperature. On coolers with an integrated fan controller, the fan was set at the full speed.
| Cooler | Room Temp. | Noise | Speed | Core Temp. | Temp. Diff. |
| Cooler Master Hyper TX3 | 18 °C | 50 dBA | 2850 rpm | 69 °C | 51 °C |
| Corsair A70 | 23 °C | 51 dBA | 2000 rpm | 66 °C | 43 °C |
| Corsair H100 | 26 °C | 62 dBA | 2000 rpm | 64 °C | 38 °C |
| EVGA Superclock | 26 °C | 57 dBA | 2550 rpm | 67 °C | 41 °C |
| NZXT HAVIK 140 | 20 °C | 46 dBA | 1250 rpm | 65 °C | 45 °C |
| Thermalright True Spirit 120 | 26 °C | 42 dBA | 1500 rpm | 82 °C | 56 °C |
| Zalman CNPS12X | 26 °C | 43 dBA | 1200 rpm | 71 °C | 45 °C |
| Zalman CNPS9900 Max | 20 °C | 51 dBA | 1700 rpm | 62 °C | 42 °C |
| Titan Fenrir Siberia Edition | 22 °C | 50 dBA | 2400 rpm | 65 °C | 43 °C |
| SilenX EFZ-120HA5 | 18 °C | 44 dBA | 1500 rpm | 70 °C | 52 °C |
| Noctua NH-L12 | 20 °C | 44 dBA | 1450 rpm | 70 °C | 50 °C |
| Zalman CNPS8900 Extreme | 21 °C | 53 dBA | 2550 rpm | 71 °C | 50 °C |
| Gamer Storm Assassin | 15 °C | 48 dBA | 1450 rpm | 58 °C | 43 °C |
| Deepcool Gammaxx 400 | 15 °C | 44 dBA | 1500 rpm | 60 °C | 45 °C |
| Cooler Master TPC 812 | 23 °C | 51 dBA | 2350 rpm | 66 °C | 43 °C |
| Deepcool Gammaxx 300 | 18 °C | 43 dBA | 1650 rpm | 74 °C | 56 °C |
| Intel stock cooler | 18 °C | 41 dBA | 2000 rpm | 97 °C | 79 °C |
| Xigmatek Praeton | 19 °C | 52 dBA | 2900 rpm | 83 °C | 64 °C |
| Noctua NH-U12P SE2 | 18 °C | 42 dBA | 1300 rpm | 69 °C | 51 °C |
| Deepcool Frostwin | 24 °C | 46 dBA | 1650 rpm | 78 °C | 54 °C |
| Thermaltake Frio Advanced | 13 °C | 56 dBA | 2000 rpm | 62 °C | 49 °C |
| Xigmatek Dark Knight Night Hawk Edition | 9 °C | 48 dBA | 2100 rpm | 53 °C | < font size="1">44 °C |
| Thermaltake Frio Extreme | 21 °C | 53 dBA | 1750 rpm | 59 °C | 38 °C |
| Noctua NH-U9B SE2 | 12 °C | 44 dBA | 1700 rpm | 64 °C | 52 °C |
| Thermaltake WATER2.0 Pro | 15 °C | 54 dBA | 2000 rpm | 52 °C | 37 °C |
| Deepcool Fiend Shark | 18 °C | 45 dBA | 1500 rpm | 74 °C | 56 °C |
| Arctic Freezer i30 | 13 °C | 42 dBA | 1350 rpm | 63 °C | 50 °C |
| Spire TME III | 8 °C | 46 dBA | 1700 rpm | 70 °C | 62 °C |
| Thermaltake WATER2.0 Performer | 11 °C | 54 dBA | 2000 rpm | 49 °C | 38 °C |
| Arctic Alpine 11 PLUS | 11 °C | 45 dBA | 2000 rpm | 82 °C | 71 °C |
| be quiet! Dark Rock 2 | 10 °C | 41 dBA | 1300 rpm | 58 °C | 48 °C |
| Phanteks PH-TC14CS | 16 °C | 47 dBA | 1300 rpm | 58 °C | 42 °C |
| Phanteks PH-TC14PE | 16 °C | 48 dBA | 1300 rpm | 57 °C | 41 °C |
| SilverStone HE01 (Q) | 19 °C | 44 dBA | 1150 rpm | 63 °C | 44 °C |
| SilverStone HE01 (P) | 20 °C | 57 dBA | 2050 rpm | 62 °C | 42 °C |
| Thermaltake WATER2.0 Extreme (S) | 17 °C | 44 dBA | 1250 rpm | 52 °C | 35 °C |
| Thermaltake WATER2.0 Extreme (E) | 17 °C | 53 dBA | 1900 rpm | 50 °C | 33 °C |
| Deepcool Neptwin | 11 °C | 46 dBA | 1500 rpm | 56 °C | 45 °C |
| SilverStone HE02 | 19 °C | 49 dBA | 2000 rpm | 64 °C | 45 °C |
| Zalman CNPS9900DF | 23 °C | 45 dBA | 1400 rpm | 68 °C | 45 °C |
| Deepcool ICE BLADE PRO V2.0 | 22 °C | 43 dBA | 1500 rpm | 67 °C | 45 °C |
| Phanteks PH-TC90LS | 24 °C | 47 dBA | 2600 rpm | 95 °C | 71 °C |
| Rosewill AIOLOS | 20 °C | 40 dBA | 1600 rpm | 94 °C | 74 °C |
| Corsair H60 | 20 °C | 49 dBA | 2000 rpm | 64 °C | 44 °C |
| Zalman LQ310 | 27 °C | 51 dBA | 2050 rpm | 65 °C | 38 °C |
| Noctua NH-L9i | 24 °C | 44 dBA | 2500 rpm | 95 °C | 71 °C |
In the graph below, you can see how many degrees Celsius hotter the CPU core is than the air outside the case. The lower this difference, the better is the performance of the cooler.
In the graph below, you can see how many decibels of noise each cooler makes.
[nextpage title=”Main Specifications”]
The main specifications for the Noctua NH-L9i CPU cooler include:
- Application: Sockets LGA1155 and LGA1156
- Dimensions: 3.7 x 3.7 x 1.5 inches (95 x 95 x 37 mm) (W x L x H)
- Fins: Aluminum
- Base: Nickel-plated copper
- Heat-pipes: Two copper heatpipes
- Fan: 92 mm
- Nominal fan speed: 2,500 rpm
- Fan air flow: 33.84 cfm
- Power consumption: 2.52 W
- Nominal noise level: 23.6 dBA
- Weight: 14.82 oz (420 g)
- More information: https://www.noctua.at/
- Average Price in the U.S.*: USD 48.00
* Researched at Newegg.com on the day we published this review.
[nextpage title=”Conclusions”]
The Noctua NH-L9i is a very well-made, low-profile CPU cooler, with the same construction quality we are accustomed to seeing in other coolers from this manufacturer.
However, there is no point in comparing the cooling performance of such a low-profile cooler to the high-end tower coolers. Therefore, we must pay attention to the data comparing the portrayed cooler to the stock cooler and other low-profile models.
The NH-L9i is shorter than the Xigmatek Praeton, the Phanteks PH-TC90LS, and the stock cooler. It performed better than the stock cooler, had a performance equivalent to the PH-TC90LS’s, but presented worse performance than the Praeton. It was, however, quieter than those retail coolers, being almost as silent as the stock cooler.
So, if you are building a PC (or an HTPC) in an SFF case and looking for a really low-profile and quiet cooler with better performance than the stock cooler, the Noctua NH-L9i is a product to consider.