LaurX

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Hello, guys! So I bought a pre-built custom water loop PC, It's been a year since then and I decided to change the liquid and clean all the tubes etc.
When I saw that my water pump has only 1 (4 pin) connector which connects into MB, I was wondering how to connect this connector directly to PSU to be able to refill my loop...

My PSU: https://www.amazon.com/CORSAIR-Modular-Supply-Platinum-Certified/dp/B00A0HZMEM

I added a picture of pump's connector: View: https://imgur.com/a/3qWVk7Q


Thank you, guys!
 
Solution
No, it's not.

You are under some misguided notion that you cannot change things. All you need is something that plugs into a molex chain from the psu and any fan connector on the other end. If the shroud is in the way, remove it, it's just a stupid piece of plastic cover. Then plug the pins directly into your pump. Simple.

Just peel that black connector like an apple, leave the pins (core) alone.

The one you already had (from picture above) will work just fine.

fry178

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just unplug all your (hdd/ssd) drives so it wont try to boot, and leave it plugged in on the cpu fan connector.
use the power button to turn it on and run it a few sec, turn off with (psu) power switch,
rinse and repeat ;-)
 

LaurX

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just unplug all your (hdd/ssd) drives so it wont try to boot, and leave it plugged in on the cpu fan connector.
use the power button to turn it on and run it a few sec, turn off with (psu) power switch,
rinse and repeat ;-)

Thanks for reply, but do I need to disconnect ALL of the cables (CPU for example) and leave only the pump connected to the MB ? And I have a PUMP connector on my MB too.
 

Aeacus

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Despite the fact the molex to fan adapter has only 2x pins at the fan connector end, it still works.

4-pin fan connector pinout:
Pin #1: +12V (for power)
Pin #2: ground
Pin #3: RPM (to read RPMs)
Pin #4: PWM (for PWM control)

All 3-pin and 4-pin fans and other hardware that use the same connector (e.g your pump) work fine with only 2-pin fan connector. Downside is that they work at full speed.
 

LaurX

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Despite the fact the molex to fan adapter has only 2x pins at the fan connector end, it still works.

4-pin fan connector pinout:
Pin #1: +12V (for power)
Pin #2: ground
Pin #3: RPM (to read RPMs)
Pin #4: PWM (for PWM control)

All 3-pin and 4-pin fans and other hardware that use the same connector (e.g your pump) work fine with only 2-pin fan connector. Downside is that they work at full speed.
Thanks, you explained a lot to me in this reply, but how do I stick a 4 pin into a 2 pin slot ? :D
 

Aeacus

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Just plug the connector in it. In the adapter side, fan connector is missing 3rd and 4th pin while the connector size is same.

Like so, look at 4-pin on 3-pin header image:
OI8N5cH.jpg
 

LaurX

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Just plug the connector in it. In the adapter side, fan connector is missing 3rd and 4th pin while the connector size is same.

Like so, look at 4-pin on 3-pin header image:
OI8N5cH.jpg

Okay, I understand you, but the problem is that the 2 pin connector is only meant for 2 pin connection. The connector looks like the first link you posted of amazon...
 

fry178

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leave all other stuff likeMB/cpu power cords connected, only disconnect the hdd/ssd drives, so it wont try to boot,
this way turning it off wont corrupt drive/OS.

yeah, its only plus/ground, no readout/control signal
 

Aeacus

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Powering on PC without any storage drives won't do harm to MoBo. Modern MoBos also boot directly to BIOS if there are no OS to boot into.

However, powering the PC on without CPU cooling is very risky since CPU will get hot and fast. Though, you can monitor CPU temps within BIOS. Btw, i'd use only PSU and molex to fan adapter to fill the open loop. No risk frying CPU this way.

The image you posted is female 4-pin fan header. To power whatever is the other end of it, you have 2 choices:
  1. Connect it to MoBo fan header and power on the whole system (as suggested by fry178)
  2. Use molex to fan adapter and use only PSU to power the pump (suggested by me)

Also, who said that the male 2-pin fan connector is meant only for 2-pin fans? Reason why the adapter has only 2 pins and not 4 is because 3rd pin is for RPM feedback, where PSU has no way showing you fan speed and 4th pin is for PWM control where PSU doesn't output the PWM signal, so the 3rd and 4th pins are missing. Regardless of that, fan/pump will still operate at normal level since pin 1 and 2 give it the power.
 

LaurX

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Powering on PC without any storage drives won't do harm to MoBo. Modern MoBos also boot directly to BIOS if there are no OS to boot into.

However, powering the PC on without CPU cooling is very risky since CPU will get hot and fast. Though, you can monitor CPU temps within BIOS. Btw, i'd use only PSU and molex to fan adapter to fill the open loop. No risk frying CPU this way.

The image you posted is female 4-pin fan header. To power whatever is the other end of it, you have 2 choices:
  1. Connect it to MoBo fan header and power on the whole system (as suggested by fry178)
  2. Use molex to fan adapter and use only PSU to power the pump (suggested by me)
Also, who said that the male 2-pin fan connector is meant only for 2-pin fans? Reason why the adapter has only 2 pins and not 4 is because 3rd pin is for RPM feedback, where PSU has no way showing you fan speed and 4th pin is for PWM control where PSU doesn't output the PWM signal, so the 3rd and 4th pins are missing. Regardless of that, fan/pump will still operate at normal level since pin 1 and 2 give it the power.

With "It's meant only for 2-pin" I mean this... It can't fit in.

View: https://imgur.com/a/8XrVXNX
 

Aeacus

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What you have is molex to 3-pin fan adapter and that one yes, doesn't do. However, there are also molex to 4-pin fan adapters out there which work for you. I linked one such adapter above (in my 1st reply).

From amazon listing:
Power Two 3-Pin or 4-Pin (PWM Connector) PC Case Fans With A Molex Connector
 

LaurX

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What you have is molex to 3-pin fan adapter and that one yes, doesn't do. However, there are also molex to 4-pin fan adapters out there which work for you. I linked one such adapter above (in my 1st reply).

From amazon listing:

Okay, so I got this thing that came with PC (shown in link below). It connects straight to PSU with molex. Could I connect my pump to this device?

https://www.nzxt.com/products/internal-usb-hub
 
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fry178

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@briedislauris
wont hurt the board, if, it would only be a problem with the cpu, but only if running it for more than 1 min.
as long as the cooling block is installed and you only power it in short intervals, you will be fine.
i once forgot to plug my pump back in and on idle power (running browser) it run for 30 min before i saw it,
temps were fine (below 70* running 3770K), but the loop was filled already, so a bit different.

just try it, unplug all power going from psu to the board, and it wont be a problem.
make sure not to run the pump for more than couple of seconds (without it moving water), to prevent (possibly) burning it out (still rare).
 
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LaurX

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@briedislauris
wont hurt the board, if, it would only be a problem with the cpu, but only if running it for more than 1 min.
as long as the cooling block is installed and you only power it in short intervals, you will be fine.
i once forgot to plug my pump back in and on idle power (running browser) it run for 30 min before i saw it,
temps were fine (below 70* running 3770K), but the loop was filled already, so a bit different.

just try it, unplug all power going from psu to the board, and it wont be a problem.
make sure not to run the pump for more than couple of seconds (without it moving water), to prevent (possibly) burning it out (still rare).

Will definetely try this when I'm more expierenced in liquid cooling, but for now, I think I am going to search for a molex adapter since it's my first time. 😁 Don't wanna risk with IX Formula mb... :/
But thanks for advice! ;)
 

Aeacus

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The one you linked has 3-pin fan connector on the other end and it's no different from the one you already have (at the 2nd image you posted).

You need to look for specific molex to fan adapter.
E.g this one at amazon.de: https://www.amazon.de/Pack-4-Pin-Molex-Splitter-Kabel-2-12-inch-30cm/dp/B07FHYMWX4
or this one at amazon.de: https://www.amazon.de/Poppstar-Verlängerungskabel-Anschluss-Gehäuselüftern-Netzteil/dp/B07Q4VW953
this one is the cheapest at amazon.de: https://www.amazon.de/ARCTIC-Molex-Lüfter-Adapter-Netzteil/dp/B00IEYEQ5E
 

LaurX

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The one you linked has 3-pin fan connector on the other end and it's no different from the one you already have (at the 2nd image you posted).

You need to look for specific molex to fan adapter.
E.g this one at amazon.de: https://www.amazon.de/Pack-4-Pin-Molex-Splitter-Kabel-2-12-inch-30cm/dp/B07FHYMWX4
or this one at amazon.de: https://www.amazon.de/Poppstar-Verlängerungskabel-Anschluss-Gehäuselüftern-Netzteil/dp/B07Q4VW953
this one is the cheapest at amazon.de: https://www.amazon.de/ARCTIC-Molex-Lüfter-Adapter-Netzteil/dp/B00IEYEQ5E

Okay, so it costs 6 Euro + Shipping = 14 Euro. I found one from local store, ordered it, hope it's the right one - https://lukass.lv/datortehnika/vadi...1x-4pin-pwm-na-3x-4pin-pwm-ak-cb002?p=2788897
 

Karadjgne

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No, it's not.

You are under some misguided notion that you cannot change things. All you need is something that plugs into a molex chain from the psu and any fan connector on the other end. If the shroud is in the way, remove it, it's just a stupid piece of plastic cover. Then plug the pins directly into your pump. Simple.

Just peel that black connector like an apple, leave the pins (core) alone.

The one you already had (from picture above) will work just fine.
 
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Solution

LaurX

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Jan 24, 2018
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No, it's not.

You are under some misguided notion that you cannot change things. All you need is something that plugs into a molex chain from the psu and any fan connector on the other end. If the shroud is in the way, remove it, it's just a stupid piece of plastic cover. Then plug the pins directly into your pump. Simple.

Just peel that black connector like an apple, leave the pins (core) alone.

The one you already had (from picture above) will work just fine.

Thank you for your reply, will try it tomorrow, I will update! :)
 

fry178

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the only thing you really need is a molex with the wires still attached and use ground/power to connect the pins to,
even if its just the wires with the ends a little stripped.
if you dont need one of the psu cables you can even use that.

i would even go so far to just attach ground (fixed) and you would only hold the wire on the 12v pin for as long as you want the pump to run (instead of turning psu on/off all the time).

molex layout
 
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