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Both links of your fans redirect to 403 error.
One thing worth mentioning about the Noiseblockers, even though they are superb fans in terms of quality, they are not that great on PWM in terms of control, the fans PWM design is meant to reach their lowest at 0% PWM, here is an example on the Blackpro PLPS ran on an Asus Maximus VI Gene on FanXpert2 on a PWM header (CPU_FAN).
SPCR did review the M12-P on the Fan Roundup #6: Scythe, Noiseblocker, Antec, Nexus, Thermalright
The M12-P differs from the S1 and S2 models in being a PWM fan and having a much higher top speed. Again, the overall noise quality is similar, although, of course, it is much louder at the >1800 RPM top speed, louder than even the huge Thermalright TY170 fan by 6 dBA. At this speed, it managed to improve on the TY170's cooling by one degree. Reducing fan speed naturally reduced noise, but it did not reach "SPCR quiet" levels till the 1100 RPM point, where it matched the cooling performance of the Nexus 120 and bettered the noise by a decibel. Below that level, it posted slightly poorer numbers than its non-PWM brethren. Despite the specified 1000~2000 RPM range, FanXpert 2 had no trouble starting and running this fan at 700 RPM.
While the M12-P is a quiet fan when its speed is reduced, its noise level is not quite the equal of the non-PWM variants. Althought it might be useful in a high power rig that scales down well at lower or idle power, the relatively high noise higher RPMs makes it less interesting to SPCR audiences.
There is a lower speed version of this PWM fan, called M12-PS, with a speed range of 600~1600 RPM and SPL of 7~23 dBA. This would be much more useful for SPCR readers. NB will be tapped for samples for the next fan roundup.
Now if you dont mind 650 rpms or so as your minium, then go for the M12-PLPS, but get a motherboard that can dip on PWM to 0%, AsRock is the only one that i seen that can on pure bios (and has 2 true pwm fan headers), else Asus on FanXpert2 will also allow it, but asus motherboards only come with one true pwm fan header (CPU_FAN), so you wont be able to use a PWM pump or at least control them seperatly.
As an alternative, a very high regarded fan for overclockers and watercooling for years have been the Scythe Gentle Typhoon AP15, sadly Scythe decided to terminate the nidec production of the fans, so they are very hard to get atm. SCPR did review two versions of it, on the Fan Roundup #6: Scythe, Noiseblocker, Antec, Nexus, Thermalright
, and according to the review the AP12 was pretty good, also sold out almost everywhere, but an available version is the Scythe Gentle Typhoon 120mm x 25mm Fan - 1150 RPM (D1225C12B3AP-13)
, the range of operation should be pretty solid, i'll leave you a couple of FanXpert2 runs on CHA_FAN (Voltage controlled) on two Gentle typhoons, i expect the above to be in between.
Now if you want to remain with PWM fans, be sure to crosscheck your motherboard has two true PWM fan headers (MSI and AsRock do in most models, Asus only has one), thats if you going with PWM pump. I would probably consider also Noctua NF-F12 PWM Fan
, sadly i dont own one to show you their graph, but i expect it would be very similar to the NF-S12A PWM.
If you dont like Noctuas color scheme, I would probably give a hard look into Asus motherboard with FanXpert2 and Scythe gentle typhoons, and use a PWM pump on the CPU_FAN and the Gentle Typhoons on CHA_FAN headers 1,2,3, if you need more just use a splitter for them. Else accept noctua color scheme and go for AsRock motherboard with two true PWM fan headers and the ability to drop the fans to very low PWM % (MSI is also a good option just not as tweakable on bios on pure fan control, but its solid). If you still want to go with Noiseblockers, accepting their 650rpm restriction, be sure to get a motherboard that can drop to 0% (Asus with FanXpert2 can but only 1 true PWM fan header, and AsRock, to what i seen can go to 0% on pure bios), else you will end up with the limitations on the bios that are commonly 20 to 40% ending with the Noiseblockers spining around 1000rpms as their minimum, so be careful choosing the motherboard.
Another fans that i have liked on the past are Scythe Slipstreams, now discontinued and replaced with the Glidestreams. Personally i see these fans more for case fans than for heatsinks or rads, but Scythe usually includes this fans on their Mugen heatsinks, so might work out fine, you can check in the SPCR Scythe Mugen 4 CPU Cooler: Scythe Strikes Back
, there are two versions that i have seen, but only one i seen on retail, Scythe Glide Stream 120mm x 25mm PWM Fan - 300 ~ 1900 RPM (SY1225HB12SH-P)
Btw how what rads and pump are you planning on?