Question How many Noctua NF-P12 redux 1700 PWM can i use in 1 splitter ?

[finalygotit]

Hi,
I'm struggling with the ( only) 4 fan headers the B550 m plus provides and would like to use a cable splitter ( not a hub ) on 1 header.
I've been on a few forums and the answer is always that you can put 2 , and maybe 3 fans on 1 header.
But according to the technical specs of the Noctua NF-P12 redux 1700 fans and the ASUS mobo i find that you can easily put more than 5 and stay way lower than the max amps allowed.
Could someone ( who is a bit more into tech than i am confirm that i can use at least 5 NF-P12 redux 1700 PWM on just 1 header)
The Asus manual states that each header is good for 1 Amp and the NF-P12 fan is rated for max 1.08 W ( x 5 = 5.4 W in total ) .
On a 12 volt board that would mean only 0.45 A .
Which would mean a 55 % margin when used at full RPM .

So where does the usually accepted maximum of 2 or 3 fans come from , has it got anything to do whit the section of the splitter cable ?
Are the fan specs (max current & power) not taking in account the full spin when the system is powered on ?
What am i missing ?

 

[Phaaze88]

Input current.
https://noctua.at/en/nf-p12-redux-1700-pwm/specification
Max. input current: 0.09A
With a motherboard header rated at 1A, that means you could theoretically chain 11(0.99A) of these fans to a single header without risk of burnout.

Take this other fan as an example: https://noctua.at/en/nf-f12-industrialppc-3000-pwm/specification
Max. input current: 0.3 A
3 of these is the most that can be safely connected to a 1A header.

https://noctua.at/en/nf-a14-industrialppc-3000-pwm/specification
Max. input current: 0.55 A
... and just one of these per 1A header.