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Some months ago we tested an excellent cooler from Zalman, CNPS10X Extreme. Today we are going to review another cooler from the same family, CNPS10X Flex. Will it perform like its brother? Let’s see.
The name "Flex" stands for "Flexibility", meaning that the cooler doesn’t come with a fan, allowing the user to choose the fan that best fits his or her needs.
The box is simple, with dark and blue shades.
Inside the box we found the cooler, installation hardware, manual and a syringe of thermal compound.
In Figure 3 we can see the cooler. An amazing detail is that it supports one or two fans. Also, if your CPU hasn’t a high TDP and you have a well-ventilated case, you can use this cooler without adding any fan on it.
In the next pages we will see the cooler in details.
[nextpage title=”Zalman CNPS10X Flex”]
In Figure 4 we have a front view of CNPS10X Flex. The design is similar to CNPS10X Extreme, but with the heatpipes and fins showing their natural colors, except for the middle find, which are painted in black.
In Figure 5 we can see the rear of the cooler. You can install one or two fans (one at each side of the heatsink, improving the airflow).
In Figure 6 we have a side view, where you can notice the five heatpipes.
[nextpage title=”Zalman CNPS10X Flex (Cont’d)”]
In Figure 7 we can see the cooler top, with a black plastic cap, giving it a very nice looks.
CNPS10X Flex is compatible, according to the manufacturer’s webpage, with socket LGA775, 1156, AM3, AM2+, AM2, 939 and 754 CPUs, but our sample didn’t come with the clip for use it with sockets 939 and 754. But, frankly speaking, no one will buy a cooler like this to install on such obsolete CPU.
The clips that come with the cooler are simple and follow the same design. There is a pair of clips for Intel CPUs and another for AMD processors. In Figure 10 we can see the cooler with the Intel clips attached the base.
In Figure 11 we see the metallic backplate, which makes installation more stable and avoids the motherboard from bending due to the applied pressure. There is only one backplate used for all sockets, and all you have to do is to put the nuts in the correct place. An excellent system with plastic holders keeps the nuts in place during installation. So, the installation is very simple, even though you have to remove the motherboard from the case (unless it offers access to the solder side of the motherboard).
In Figure 12 we can see CNPS10X Flex installed on our motherboard, still without the fan. Note the thin black strips on the heatsink: they are strips of self-adhesive rubber that helps absorbing noise and vibration from the fan.
In Figure 13, you can see the cooler installed inside our case, with the fan in place.
[nextpage title=”How We Tested”]
We are adopting the following methodology for our CPU cooler reviews.
First, we chose the CPU with the highest TDP (Thermal Design Power) we had available, a Core 2 Extreme QX6850, which has a 130 W TDP. The choice for a CPU with a high TDP is obvious. To measure the efficiency of the tested cooler, we need a processor that gets very hot. This CPU works by default at 3.0 GHz, but we overclocked it to 3.33 GHz, in order to heat it as much as possible.
We took noise and temperature measurements with the CPU idle and under full load. In order to achieve 100% CPU load on the four processing cores we ran Prime95 with the "In-place Large FFTs" option, and three instances of the StressCPU program, all at the same time.
We also compared the reviewed cooler to the Intel stock cooler (with copper base), which comes with the processor we used, and also with some other coolers we have tested using the same methodology.
Temperature measurements were taken with a digital thermometer, with the sensor touching the base of the cooler, and also with the core temperature reading (given by the CPU thermal sensor) from the from the SpeedFan program, using an arithmetic average of the four core temperature readings.
The sound pressure level (SPL) was measured with a digital noise meter, with its sensor placed 4" (10 cm) from the fan. We turned off the video board cooler so it wouldn’t interfere with the results, but this measurement is only for comparative 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.
- Processor: Core 2 Extreme QX6850
- Motherboard: Gigabyte EP45-UD3L
- Memory: 4 GB G.Skill F2-6400CL5S-2GBNY (DDR2-800/PC2-6400 with 5-5-5-15 timings), configured at 800 MHz
- Hard drive: 1 TB Seagate Barracuda 7200.12 (ST31000528AS, SATA-300, 7200 rpm, 32 MB buffer)
- Video card: PNY Verto Geforce 9600 GT
- Video resolution: 1680×1050
- Video monitor: Samsung Syncmaster 2232BW Plus
- Power supply required: Seventeam ST-550P-AM
- Case: 3RSystem K100
- Windows 7 Home Premium 64 bit
We adopted a 2 °C error margin, i.e., temperature differences below 2 °C are considered irrelevant.
[nextpage title=”Our Tests”]
On the tables below you can see our results. We ran the same tests with the coolers shown on below tables. Each test ran with the CPU idle and the with the CPU fully loaded. On BigTyp 14Pro, TMG IA1, NH-U12P and ISGC-300 the tests were done with the fan at full speed and at minimum speed. The other coolers were connected directly to the motherboard and it controls the fan speed based on CPU load level and temperature on PWM models. ISGC-400, iCEAGE Prima Boss, Megahalems Rev. B, Thermaltake SpinQ VT and Zalman CNPS10X Flex were tested at minimum speed on idle test and at maximum speed on full load test.
|Cooler||Room Temp.||Noise||Fan Speed||Base Temp.||Core Temp.|
|Intel stock||14 °C||44 dBA||1000 rpm||31 °C||42 °C|
|BigTyp 14Pro (min)||17 °C||47 dBA||880 rpm||29 °C||36 °C|
|BigTyp 14Pro (max)||17 °C||59 dBA||1500 rpm||26 °C||34 °C|
|Akasa Nero||18 °C||41 dBA||500 rpm||26 °C||35 °C|
|Cooler Master V10||14 °C||44 dBA||1200 rpm||21 °C||26 °C|
|TMG IA1 (max)||16 °C||47 dBA||1500 rpm||22 °C||30 °C|
|TMG IA1 (min)||16 °C||57 dBA||2250 rpm||21 °C||30 °C|
|Zalman CNPS10X Extreme||16 °C||44 dBA||1200 rpm||21 °C||29 °C|
|Thermaltake ISGC-100||18 °C||44 dBA||1450 rpm||35 °C||49 °C|
|Noctua NH-U12P (low)||15 °C||42 dBA||1000 rpm||20 °C||30 °C|
|Noctua NH-U12P||15 °C||46 dBA||1400 rpm||20 °C||28 °C|
|Noctua NH-C12P||17 &
|46 dBA||1400 rpm||23 °C||28 °C|
|Thermaltake ISGC-200||21 °C||43 dBA||1100 rpm||31 °C||35 °C|
|Schythe Kabuto||22 °C||42 dBA||800 rpm||29 °C||34 °C|
|Arctic Cooling Alpine 11 Pro||20 °C||43 dBA||1500 rpm||32 °C||39 °C|
|ISGC-300 (min)||18 °C||42 dBA||800 rpm||26 °C||30 °C|
|ISGC-300 (max)||18 °C||46 dBA||1400 rpm||24 °C||26 °C|
|SilverStone NT06-E||21 °C||66 dBA||2600 rpm||30 °C||41 °C|
|Zalman CNPS9700 NT||22 °C||48 dBA||1700 rpm||28 °C||35 °C|
|Scythe Mugen-2||17 °C||41 dBA||700 rpm||25 °C||30 °C|
|ISGC-400 (min)||17 °C||44 dBA||850 rpm||24 °C||30 °C|
|Cooler Master Vortex 752||20 °C||48 dBA||1700 rpm||32 °C||44 °C|
|iCEAGE Prima Boss (min)||22 °C||42 dBA||1000 rpm||29 °C||36 °C|
|Evercool Buffalo||17 °C||51 dBA||1850 rpm||22 °C||29 °C|
|Scythe Big Shuriken||20 °C||42 dBA||900 rpm||31 °C||39 °C|
|Cooler Master Hyper TX3||21 °C||44 dBA||1700 rpm||30 °C||39 °C|
|Titan Skalli||20 °C||43 dBA||1200 rpm||27 °C||34 °C|
|Prolimatech Megahalems Rev. B||21 °C||40 dBA||800 rpm||28 °C||32 °C|
|Zalman CNPS9900 NT||23 °C||45 dBA||900 rpm||30 °C||34 °C|
|Cooler Master Hyper N620||21 °C||44 dBA||1200 rpm||28 °C||34 °C|
|Nexus LOW-7000 R2||23 °C||46 dBA||1400 rpm||33 °C||42 °C|
|Evercool HPK-10025EA||20 °C||54 dBA||1900 rpm||27 °C||34 °C|
|Evercool HPH-9525EA||23 °C||50 dBA||1900 rpm||38 °C||49 °C|
|iCEAGE Prima Boss II||23 °C||42 dBA||1000 rpm||29 °C||35 °C|
|Thermaltake SpinQ VT||24 °C||45 dBA||950 rpm||32 °C||39 °C|
|Titan Fenrir||21 °C||42 dBA||950 rpm||29 °C||35 °C|
|Zalman CNPS 10 Flex||23 °C||40 dBA||800 rpm||32 °C||39 °C|
CPU Fully Loaded
|Cooler||Room Temp.||Noise||Fan Speed||Base Temp.||Core Temp.|
|Intel stock||14 °C||48 dBA||1740 rpm||42 °C||100 °C|
|BigTyp 14Pro (min)||17 °C||47 dBA||880 rpm||43 °C||77 °C|
|BigTyp 14Pro (max)||17 °C||59 dBA||1500 rpm||35 °C||70 °C|
|Akasa Nero||18 °C||48 dBA||1500 rpm||34 °C||68 °C|
|Cooler Master V10||14 °C||54 dBA||1900 rpm||24 °C||52 °C|
|TMG IA1 (max)||16 °C||47 dBA||1500 rpm||27 °C||63 °C|
|TMG IA1 (min)||16 °C||57 dBA||2250 rpm||25 °C||60 °C|
|Zalman CNPS10X Extreme||16 °C||51 dBA||1900 rpm||24 °C||50 °C|
|Thermaltake ISG-100||18 °C||50 dBA||1800 rpm||58 °C||93 °C|
|Noctua NH-U12P (low)||15 °C||42 dBA||1000 rpm||28 °C||59 °C|
|Noctua NH-U12P||15 °C||46 dBA||1400 rpm||25 °C||54 °C|
|Noctua NH-C12P||17 °C||46 dBA||1400 rpm||37 °C||76 °C|
|Thermaltake ISGC-200||21 °C||48 dBA||1900 rpm||42 °C||68 °C|
|Scythe Kabuto||22 °C||47 dBA||1200 rpm||38 °C||63 °C|
|Arctic Cooling Alpine 11 Pro||20 °C||51 dBA||2300 rpm||49 °C||85 °C|
|ISGC-300 (min)||18 °C||42 dBA||800 rpm||36 °C||64 °C|
|ISGC-300 (max)||18 °C||46 dBA||1400 rpm||31 °C||56 °C|
|SilverStone NT06-E||21 °C||66 dBA||2600 rpm||39 °C||96 °C|
|Zalman CNPS9700 NT||22 °C||56 dBA||2600 rpm||34 °C||63 °C|
|Scythe Mugen-2||17 °C||46 dBA||1300 rpm||28 °C||54 °C|
|ISGC-400 (max)||17 °C||47 dBA||1400 rpm||36 °C||69 °C|
|Cooler Master Vortex 752||20 °C||55 dBA||2300 rpm||48 °C||92 °C|
|iCEAGE Prima Boss (max)||22 °C||53 dBA||2000 rpm||35 °C||59 °C|
|Evercool Buffalo||17 °C||51 dBA||1850 rpm||32 °C||67 °C|
|Scythe Big Shuriken||20 °C||50 dBA||1500 rpm||51 °C||85 °C|
|Cooler Master Hyper TX3||21 °C||53 dBA||2700 rpm||39 °C||66 °C|
|Titan Skalli||20 °C||47 dBA||1550 rpm||37 °C||69 °C|
|Prolimatech Megahalems Rev. B||21 °C||61 dBA||2600 rpm||30 °C||51 °C|
|Zalman CNPS9900 NT||23 °C||56 dBA||2000 rpm||34 °C||54 °C|
|Cooler Master Hyper N620||21 °C||50 dBA||1650 rpm||32 °C||56 °C|
|Nexus LOW-7000 R2||23 °C||53 dBA||1900 rpm||45 °C||74 °C|
|Evercool HPK-10025EA||20 °C||54 dBA||1900 rpm||39 °C||69 °C|
|Evercool HPH-9525EA||23 °C||50 dBA||1900 rpm||58 °C||100 °C|
|iCEAGE Prima Boss II||23 °C||56 dBA||2100 rpm||32 °C||56 °C|
|Thermaltake SpinQ VT||24 °C||52 dBA||1500 rpm||40 °C||68 °C|
|Titan Fenrir||21 °C||50 dBA||1600 rpm||33 °C||58 °C|
|Zalman CNPS 10 Flex||23 °C||61 dBA||2600 rpm||33 °C||59 °C|
The next graph shows how many degrees Celsius the CPU core was hotter than room temperature during our idle tests.
The next graph gives you an idea on how many degrees Celsius the CPU core was hotter than room temperature during our full load tests.
[nextpage title=”Main Specifications”]
Zalman CNPS10X Flex main features are:
- Application: Socket LGA775, 1156, 1366, AM3, AM2+ and AM2 processors.
- Fins: Aluminum.
- Base: Copper.
- Heat-pipes: Five U-shaped copper heat-pipes.
- Fan: One or two, 120 mm (not included).
- Nominal fan speed: N/A.
- Fan air flow: N/A.
- Maximum power consumption: N/A.
- Nominal noise level: N/A.
- Weight: 1.5 lbs (700 g).
- More information: https://www.zalman.com
- Average price in the US*: USD 52.00
* Researched at newegg.com on the day we published this review.
When we tested CNPS10X Extreme a few months ago we were very impressed by its rock-solid aspect and by its performance. Today testing its "little brother" we also liked the results. Although CNPS10X Flex is not as beautiful as its most expensive brother – at least in our opinion, but taste is a very personal matter -, it performed practically the same as the other model.
You must keep in mind, however, that even being less expensive than CNPS10X Extreme, you still need to buy a good fan (or even two) in order to use it. At the end, it is not an inexpensive solution.
How the cooler will look inside your case will depend on the fan you pick, from a classic black one to a multicolor LED fan. So, this product has a reason for the "Flex" on its name, fitting the taste of the user.
Being a nice-looking cooler, with an easy and dependable holding system, versatile and with an excellent performance, Zalman CNPS10X Flex deserves the Hardware Secrets Silver Award.