Jump to content

PWM 4 pin and splitters?

chris-red

Hi all, quick basic question. Can you sure a 4 pin PWM splitter which 2 different types of fan?

 

My reasoning for thinking it may be an issue is one of the pins is a rotation sense/ tacho right? I would have though the output of that would be confusing if the fans were running at different speeds?

Link to comment
Share on other sites

Link to post
Share on other sites

yes but make sure that the fans are wihin 100-200 RPM of eachother 

Link to comment
Share on other sites

Link to post
Share on other sites

4 minutes ago, chris-red said:

Hi all, quick basic question. Can you sure a 4 pin PWM splitter which 2 different types of fan?

 

My reasoning for thinking it may be an issue is one of the pins is a rotation sense/ tacho right? I would have though the output of that would be confusing if the fans were running at different speeds?

As long as they are compatible they'll work, but the fan header will only give 1 speed report, you won't be able to set speed on each fan

System : AMD R9 5900X / Gigabyte X570 AORUS PRO/ 2x16GB Corsair Vengeance 3600CL18 ASUS TUF Gaming AMD Radeon RX 7900 XTX OC Edition GPU/ Phanteks P600S case /  Eisbaer 280mm AIO (with 2xArctic P14 fans) / 2TB Crucial T500  NVme + 2TB WD SN850 NVme + 4TB Toshiba X300 HDD drives/ Corsair RM850x PSU/  Alienware AW3420DW 34" 120Hz 3440x1440p monitor / Logitech G915TKL keyboard (wireless) / Logitech G PRO X Superlight mouse / Audeze Maxwell headphones

Link to comment
Share on other sites

Link to post
Share on other sites

8 minutes ago, chris-red said:

Hi all, quick basic question. Can you sure a 4 pin PWM splitter which 2 different types of fan?

 

My reasoning for thinking it may be an issue is one of the pins is a rotation sense/ tacho right? I would have though the output of that would be confusing if the fans were running at different speeds?

A correct splitter for this, such as what Noctua sell, only connects the tachometer pin to one of the fans.  I've used them extensively due to having several ITX builds and one of the motherboards had a flawed case fan header which didn't change fan speeds, so I connected the case fan alongside the CPU fan.

Router:  Intel N100 (pfSense) WiFi6: Zyxel NWA210AX (1.7Gbit peak at 160Mhz) WiFi5: Ubiquiti NanoHD OpenWRT (~500Mbit at 80Mhz)

Switches: Netgear MS510TXUP, Netgear MS510TXPP, Netgear GS110EMX
ISPs: Zen Full Fibre 900 (~930Mbit down, 115Mbit up) + Three 5G (~800Mbit down, 115Mbit up)
Upgrading Laptop/Desktop CNVIo WiFi 5 cards to PCIe WiFi6e/7

Link to comment
Share on other sites

Link to post
Share on other sites

6 minutes ago, Alex Atkin UK said:

A correct splitter for this, such as what Noctua sell, only connects the tachometer pin to one of the fans.

I've bought a five pack somewhere on the internet and it was the same way, all of them work great, even with entirely different fans.

Trans Rights!
Please tag me or use the "reply" function so I get a notification

I will find your Laptop thread and I will recommend an ITX build instead

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Sure would be neat if there was something useful here, eh?

Link to comment
Share on other sites

Link to post
Share on other sites

1 minute ago, Bismut said:

I've bought a five pack somewhere on the internet and it was the same way, all of them work great, even with entirely different fans.

Yeah the Noctua are really expensive for what they are, but I wanted to be sure I got something with a sensible wire gauge as random stuff you never know if it can really handle the current rating you are potentially pulling.  I try to always avoid anything unbranded if its going inside my PC and has the potential for fire. 😉

Router:  Intel N100 (pfSense) WiFi6: Zyxel NWA210AX (1.7Gbit peak at 160Mhz) WiFi5: Ubiquiti NanoHD OpenWRT (~500Mbit at 80Mhz)

Switches: Netgear MS510TXUP, Netgear MS510TXPP, Netgear GS110EMX
ISPs: Zen Full Fibre 900 (~930Mbit down, 115Mbit up) + Three 5G (~800Mbit down, 115Mbit up)
Upgrading Laptop/Desktop CNVIo WiFi 5 cards to PCIe WiFi6e/7

Link to comment
Share on other sites

Link to post
Share on other sites

3 minutes ago, Alex Atkin UK said:

I try to always avoid anything unbranded if its going inside my PC and has the potential for fire.

Why, do you not want to burn your house down or something? Lame! ^^

I do understand the rational though, but my fans only draw about 0.2A and I avoid daisy chaining them, so the risk is acceptable to me. I wouldn't want to get unbranded 12V PCIe extensions, that just sounds like a bad idea.

Trans Rights!
Please tag me or use the "reply" function so I get a notification

I will find your Laptop thread and I will recommend an ITX build instead

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Sure would be neat if there was something useful here, eh?

Link to comment
Share on other sites

Link to post
Share on other sites

2 hours ago, Alex Atkin UK said:

A correct splitter for this, such as what Noctua sell, only connects the tachometer pin to one of the fans.  I've used them extensively due to having several ITX builds and one of the motherboards had a flawed case fan header which didn't change fan speeds, so I connected the case fan alongside the CPU fan.

Great thanks, They are Noctua fans so that will be good, its a bit of a custom job involving 1x 120mm and 2x40mm fans all coming form a single header, I assumed there will be a noticeable difference between the fans speed.

Link to comment
Share on other sites

Link to post
Share on other sites

9 minutes ago, chris-red said:

I assumed there will be a noticeable difference between the fans speed

That could be, 5000/2=2500 and 2500/2=1250, if 50% duty cycle corresponds to 50% speed. There's those low noise adapters though, you could put one of those before the 40mms.

Trans Rights!
Please tag me or use the "reply" function so I get a notification

I will find your Laptop thread and I will recommend an ITX build instead

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Sure would be neat if there was something useful here, eh?

Link to comment
Share on other sites

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×