Zalman FX100 CPU Cooler Review
By Rafael Coelho on March 20, 2013
The Zalman FX100 is a fanless CPU cooler with a huge cube heatsink and 10 heatpipes. Let’s test it with no fan, and also with one optional 92 mm fan, and see if it can cool our CPU. Check it out!
Although being advertised as a truly fanless CPU cooler, Zalman says that the use of an optional 92 mm fan is required when used with a socket LGA1366 or socket LGA2011 CPU. Actually, the product documentation says that it supports CPUs with a TDP up to 130 W when a fan is used, but there is no information about how many watts the FX100 supports in fanless operation.
Figure 1 shows the huge box of the FX100.
Figure 2 shows the contents of the box: the cooler, a small bag of thermal compound, a manual, and installation hardware. This cooler does not come with any fan.
Figure 3 displays the front of the cooler.
This cooler is discussed in detail in the following pages.
Figure 4 illustrates the side of the Zalman FX100. Here you can see the curves of the heatpipes.
Figure 5 reveals the rear of the cooler. Notice that there are actually four heatpipes going through the base.
Figure 6 shows a top view of the cooler, which is closed by a removable meshed plate.
Figure 7 unveils the bottom of the cooler. Two heatpipes go for the corners of the heatsink and two enter in the middle, where there are two independent heatsinks.
Figure 8 shows the base of the cooler. It is a nickel-plated copper plate with mirrored finishing.
Removing the top cap, you can obtain a better idea of how the FX100 is made; there are four heatsinks at the sides, and two smaller heatsinks at the center. The optional fan goes between the inner heatsinks.
Figure 10 unveils the FX100 without the plastic corners. Here you can see the six heatpipes that surround the cooler. Those heatpipes are soldered to the heatpipes that come from the base.
Figure 11 shows the backplate for use with AMD and Intel processors, except for socket LGA2011 CPUs, with the nuts installed.
Install the backplate on the solder side of the motherboard, and then the four spacers on the component side. Then place the two metal bars shown in Figure 12, holding them with four thumbnuts.
The next step is a little tricky: you need to remove the cover from the cooler, put the heatsink over the CPU, and hold it in place with a third bar, fastening two screws at the first bars. But this bar and those screws are loose, and you need a very long Phillips screwdriver to fasten them, taking extra care so they do not fall from the holes.
After installing the heatsink, put the cover back in place. At the end of the process, it was one of the most annoying mounting systems we ever saw.
We tested the FX100 without any fan, and also with a 92 mm fan, which we removed from a Cooler Master Hyper TX3 cooler we had on hand. This fan has 2,800 rpm nominal speed, airflow of 54.8 cfm, 35 dBA of noise level, and 3.12 W power consumption. Figure 15 shows the cooler with the fan installed.
We detected a little mounting problem with the Zalman FX100: as shown in Figure 16, the transversal bar is too long and touched the heatsinks of the motherboard. The cooler was firmly installed, but it may have lost a little pressure because of this problem.
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.
Operating System Configuration
We adopted a 2°C error margin, meaning temperature differences below 2°C are considered irrelevant.
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 ºC||51 °C|
|Corsair A70||23 °C||51 dBA||2000 rpm||66 ºC||43 °C|
|Corsair H100||26 °C||62 dBA||2000 rpm||64 ºC||38 °C|
|EVGA Superclock||26 °C||57 dBA||2550 rpm||67 ºC||41 °C|
|NZXT HAVIK 140||20 °C||46 dBA||1250 rpm||65 ºC||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||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|
|NZXT Respire T40||20 °C||45 dBA||1850 rpm||76 °C||56 °C|
|NZXT Respire T20||21 °C||45 dBA||1900 rpm||77 °C||56 °C|
|Zalman LQ315||20 °C||52 dBA||1950 rpm||57 °C||37 °C|
|Corsair H80i (Quiet)||19 °C||44 dBA||1100 rpm||61 °C||42 °C|
|Corsair H80i (Maximum)||19 °C||57 dBA||2500 rpm||55 °C||36 °C|
|NZXT Kraken X40 (Silent)||25 °C||44 dBA||1050 rpm||66 °C||41 °C|
|NZXT Kraken X40 (Extreme)||25 °C||53 dBA||1650 rpm||62 °C||37 °C|
|Zalman LQ320||20 °C||52 dBA||2100 rpm||57 °C||37 °C|
|Corsair H100i (Quiet)||22 °C||45 dBA||1150 rpm||58 °C||36 °C|
|Corsair H100i (Maximum)||22 °C||61 dBA||2500 rpm||54 °C||32 °C|
|NZXT Kraken X60 (Silent)||26 °C||46 dBA||1000 rpm||62 °C||36 °C|
|NZXT Kraken X60 (Extreme)||26 °C||60 dBA||1650 rpm||60 °C||34 °C|
|Prolimatech Genesis Black Series||25 °C||46 dBA||1150 rpm||69 °C||44 °C|
|Phanteks PH-TC12DX||25 °C||51 dBA||1850 rpm||74 °C||49 °C|
|Corsair H90||23 °C||51 dBA||1550 rpm||61 °C||38 °C|
|Corsair H110||27 °C||58 dBA||1500 rpm||60 °C||33 °C|
|Evercool Venti||23 °C||49 dBA||2250 rpm||72 °C||49 °C|
|Thermalright Archon SB-E X2||22 °C||45 dBA||1400 rpm||68 °C||46 °C|
|Scythe Kabuto II||20 °C||41 dBA||1450 rpm||67 °C||47 °C|
|Prolimatech Megahalems Red Series||20 °C||51 dBA||1500 rpm||63 °C||43 °C|
|Zalman FX100 (fanless)||18 °C||NA||NA||98 °C||80 °C|
|Zalman FX100 (92 mm fan)||18 °C||50 DBA||2850 rpm||69 °C||51 °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.
The main specifications for the Zalman FX100 CPU cooler include:
After testing the Zalman FX100, one thing seems to be clear to us: there is no fanless cooler capable of cooling a high-end CPU, especially if it is overclocked. Even with all its size, the FX100 showed a barely reasonable cooling performance with a noisy fan installed.
Mounted with no fan, the FX100 didn’t handle our CPU, even considering it has a very light overclocking and that there was a case exhaust fan at the rear panel, very close to the cooler. The CPU reached the temperature limit and throttled down the clock. Maybe it can cool a low-TDP processor, but it seems pointless to install such a huge cooler if even the stock cooler cools the CPU better, with a very low noise level.
The Zalman FX100 was a complete disappointment. It may have a stunning look, but the installation system and the cooling performance have much to be improved.