5v fan headers - why?

[Tristerin]

There is a newegg sale going on...I can get some splitters for pennies but its molex to 2x 12v fan header and 2x 5v fan header.

 

What all in the PC world is powered off 5v 2pin headers?  Just these small fans Im looking at?  Anything in particular (their winter sale right now has a bunch of stuff at pennies to the dollar and free shipping if I spend $25 or more so I plan on buying at least that amount of somethings - or multiple things) so I can grab it up in the sale?  Ive got parts coming in for a custom loop, anything for loops that use 5v? 

 

 

 

[LukeNukem9]

6 minutes ago, Tristerin said:

There is a newegg sale going on...I can get some splitters for pennies but its molex to 2x 12v fan header and 2x 5v fan header.

 

What all in the PC world is powered off 5v 2pin headers?  Just these small fans Im looking at?  Anything in particular (their winter sale right now has a bunch of stuff at pennies to the dollar and free shipping if I spend $25 or more so I plan on buying at least that amount of somethings - or multiple things) so I can grab it up in the sale?  Ive got parts coming in for a custom loop, anything for loops that use 5v? 

 

 

 

The only thing i can thinks is small enough is my fan in my raspberry pi 3 is 3.3 or 5 volts.

[BobVonBob]

Pretty much just fans. For example Noctua has a bunch of 5V fans, just search "5V" on their product page and you'll find just about every size of 5V fan out there from 40mm to 200mm.

https://noctua.at/en/products/fan

 

Other than that though most things for PCs have been designed for 12V, since that's the most common voltage in a PC nowadays.

[piemadd]

12 minutes ago, Tristerin said:

There is a newegg sale going on...I can get some splitters for pennies but its molex to 2x 12v fan header and 2x 5v fan header.

 

What all in the PC world is powered off 5v 2pin headers?  Just these small fans Im looking at?  Anything in particular (their winter sale right now has a bunch of stuff at pennies to the dollar and free shipping if I spend $25 or more so I plan on buying at least that amount of somethings - or multiple things) so I can grab it up in the sale?  Ive got parts coming in for a custom loop, anything for loops that use 5v? 

 

 

 

all they're doing is tapping into the 5v and 12v rails of the molex connector. idk what fans are powered by 5v, but thats the power which the molex connector can provide

[Tristerin]

5 minutes ago, BobVonBob said:

Pretty much just fans. For example Noctua has a bunch of 5V fans, just search "5V" on their product page and you'll find just about every size of 5V fan out there from 40mm to 200mm.

https://noctua.at/en/products/fan

 

Other than that though most things for PCs have been designed for 12V, since that's the most common voltage in a PC nowadays.

I wonder if their is a price delta, Ill have to investigate.  I need some 80mm SP fans for this project (2 80mm rads in a microtower)

 

Thanks!

[tarfeef101]

I've seen 2 pin fans before in some OEM builds, and on more specialized hardware. Generally they were < 120mm, but they're otherwise normal fans. As long as the specs line up with what you want/need, there's nothing wrong with em. You can search 2 pin PC fans on google/amazon and find relevant results

Edited February 22, 2019 by tarfeef101
lol 2 pin. i can read

[Tristerin]

1 minute ago, tarfeef101 said:

For 3-pin fans, their speed is controlled by voltage. So, you can use a 5V header to get a lower RPM that with a full 12V. This may or may not work depending on the fan (some may not operate at a voltage that low, some will), but is definitely useful in some cases.

Makes sense, like a voltage regulator.  I have some Arctic P12s that wouldn't work (because they need 60% power to start spinning up) - I see what you mean!