Please refer to following drawing for how to identify the different backplate revisions:

Some mainboards pose compatibility problems with the first version of the NM-IBP2 backplate included with the cooler. Please verify to use a revision 1.5 or revision 2 backplate when installing the cooler on these mainboards. All coolers manufactured since April 2013 already include the new revision backplates. Owners of coolers with rev. 1 backplates can request a new backplate from Noctua’s customer service free of charge.

"Le système de fixation est identique sur l'ensemble des sockets LGA115x (LGA1150, LGA1155, LGA1156). Les ventirads suivants sont donc immédiatement compatibles avec le LGA1150 et ne nécessitent aucun accessoire ni mise à jour pour une utilisation sur cette plateforme : NH-C12P SE14, NH-C14, NH-D15, NH-D14, NH-L12, NH-L9i, NH-U14S, NH-U12S, NH-U12P SE2, NH-U9B SE2. Les modèles plus anciens ayant été modifiés via le kit NM-I3 sont par ailleurs directement utilisable avec le LGA1150 et ne nécessitent donc aucune mise à jour additionnelle.

Les ventirads suivants peuvent devenir compatibles avec le LGA1150 via l’utilisation du kit NM-i115x et bénéficient de l’offre de gratuité Noctua pour le kit : NH-C12P, NH-U12, NH-U12F, NH-U12P, NH-U12P SE1366, NH-U9, NH-U9F, NH-U9B.

Les ventirads suivants peuvent devenir compatibles avec LGA1150 via l’utilisation du kit NM-i115x mais ne bénéficient pas de l’offre de gratuité Noctua pour le kit : DX-Series Xeon coolers, NH-D14 SE2011.

Les ventirads suivants ne sont pas, pour des raisons mécaniques, compatibles avec le kit NM-i115x et ne peuvent jouir d’une compatibilité avec le LGA1150: Série DO, ventirads pour AMD Opteron et NH-L9a.

Some mainboards feature 4-pin fan headers that actually don‘t use a PWM signal on Pin 4 to control the fan speed but rather reduce the voltage on Pin 2 (like a standard 3-pin fan header). In this case, it may occur that the mainboard reduces the voltage so much that the fan stops. Please refer to your mainboard manual to check whether or not your mainboard has 4-pin fan headers that control the fan speed by reducing voltage on Pin 2 rather than by changing the PWM duty cycle on Pin 4:

Note that mainboard manufacturers use different terms to indicate that Pin 4 is not being used for PWM control (e.g. “+5V”, “VCC” or “NC”), but if one of these terms is used, you can be sure that the fan header does not support PWM. If Pin 4 is described as “Speed Control” or “PWM” or the like, you can be sure that the fan header supports PWM.

Unfortunately, the description of Pin 2 is not always a clear indication as some manufacturers use terms such as “Fan PWR” or “Power” for both types of fan headers. However, if Pin 2 is described as “Speed Control”, you can also be sure that the fan header does not support PWM based speed control. If Pin 2 is described as “+12V”, this is a clear indication that the fan header supports PWM.

Please also note that in some cases, the descriptions of the pin layouts in the mainboard manuals may not be correct and some models actually allow you to switch the fan headers from voltage control mode to PWM control mode in the BIOS even though the pin descriptions do not indicate PWM support. We thus recommend to look for these options in the BIOS before taking other measures. In case of doubt, please contact your mainboard manufacturer.

To resolve the issue, you can:

1. Choose a higher fan speed profile in the BIOS (e.g. „normal“ instead of „silent“, etc.) or deactivate automatic fan speed control and use a Low-Noise Adaptor instead.
   
   

2. Use the mainboard‘s fan speed control software or 3rd party tools like Speedfan to regulate the fan speed. Unlike BIOS based fan speed control, the supplied software usually checks whether the fan has stopped and increases voltage accordingly or at least offer more options to set up the fan properly.
   
   

3. If your mainboard features other 4-pin fan headers that use PWM for speed control, you can run multiple fans from these headers using Y-split cables. Make sure not to exceed the specified maximum power draw of the fan headers (usually 10-12W) though.

The specified minimum speed refers to the speed at 20% PWM duty cycle. There can be several reasons why the fan doesn‘t go as low as indicated:

1. Many mainboards do not go below 40%, 50% or even 60% PWM duty cycle on case fan headers. Please refer to your mainboard manual to verify whether the fan header actually goes down to 20% duty cycle. If that's not the case, in some cases you can use the fan speed control software supplied with your mainboard to overcome these limitations and reduce the fan speed even further. However, 3rd party tools like SpeedFan offer greater flexibility and better options to work around the limitations imposed by the mainboard vendors.
   
   
2. Some mainboards feature 4-pin fan headers that actually don‘t use a PWM signal on Pin 4 to control the fan speed but rather reduce the voltage on Pin 2 (like a standard 3-pin fan header). As the fan speed at minimum voltage is usually higher than the speed at 20% PWM duty cycle, the fan can not reach as low minimum speeds under voltage control as under PWM control. Please refer to your mainboard manual to check whether or not your mainboard has 4-pin fan headers that control the fan speed by reducing voltage on Pin 2 rather than by changing the PWM duty cycle on Pin 4:
   
   
   
   Note that mainboard manufacturers use different terms to indicate that Pin 4 is not being used for PWM control (e.g. “+5V”, “VCC” or “NC”), but if one of these terms is used, you can be sure that the fan header does not support PWM. If Pin 4 is described as “Speed Control” or “PWM” or the like, you can be sure that the fan header supports PWM.
   
   Unfortunately, the description of Pin 2 is not always a clear indication as some manufacturers use terms such as “Fan PWR” or “Power” for both types of fan headers. However, if Pin 2 is described as “Speed Control”, you can also be sure that the fan header does not support PWM based speed control. If Pin 2 is described as “+12V”, this is a clear indication that the fan header supports PWM.
   
   Please also note that in some cases, the descriptions of the pin layouts in the mainboard manuals may not be correct and some models actually allow you to switch the fan headers from voltage control mode to PWM control mode in the BIOS even though the pin descriptions do not indicate PWM support. We thus recommend to look for these options in the BIOS before taking other measures. In case of doubt, please contact your mainboard manufacturer.
   
   If your mainboard features other 4-pin fan headers that use PWM for speed control, you can run multiple fans from these headers using Y-split cables. Make sure not to exceed the specified maximum power draw of the fan headers (usually 10-12W) though.