Understanding the MSI Motherboard - PWM Fan connectors

HBSound · Nov 6, 2023

I want to make sure, that I am preparing for an installation. This motherboard has three fan connections: CPU_FAN1, PUMP_FAN1, and SYS_FAN1. I plan on using them as follows.

CPU_FAN1 - Three Phantek 120.
PUMP_FAN1 - DCC Pump
SYS_FAN1 - Three Phantek 120.

Here are my questions in line with those connectors

CPU_FAN1 - The motherboard standard bios calls this AutoMod - Can switch this to PWM Mode?
PUMP_FAN1 - The motherboard standard bios calls in PWM Mode. How can I connect more than one pump to this connector?
SYS_FAN1 - The motherboard standard bios calls this DCMod - Can switch this to PWM Mode?

Thank you in advance.

AusWolf · Nov 6, 2023

What motherboard is that? If it's anything fairly new, then:

HBSound said:
CPU_FAN1 - The motherboard standard bios calls this AutoMod - Can switch this to PWM Mode?

It's PWM by default.

HBSound said:
PUMP_FAN1 - The motherboard standard bios calls in PWM Mode. How can I connect more than one pump to this connector?

You'll need a fan cable splitter, but make sure the pumps together don't exceed the 3 Ampere rating of the connector.

HBSound said:
SYS_FAN1 - The motherboard standard bios calls this DCMod - Can switch this to PWM Mode?

If it's 4-pin, then yes. Look for it in the BIOS.

HBSound · Nov 6, 2023

AusWolf said:
What motherboard is that? If it's anything fairly new, then:

It's PWM by default.

You'll need a fan cable splitter, but make sure the pumps together don't exceed the 3 Ampere rating of the connector.

If it's 4-pin, then yes. Look for it in the BIOS.

Thank you so much!

Vya Domus · Nov 6, 2023

but make sure the pumps together don't exceed the 3 Ampere rating of the connector.

This doesn't really matter, those pumps have molex/sata power, the cable is just for speed control.

Tatty_Two · Nov 6, 2023

On my MSI board I am pretty sure I can switch all headers to PWM mode but to answer the specific question, I have both CPU_Fan1 and the pump fan running in PWM, I have set my other fans on fixed settings.

Vya Domus · Nov 6, 2023

Pretty much all modern motherboards should have both DC and PWM for all headers, if it has 4 pins it will support both, that has been a standard for quite some time.

AusWolf · Nov 6, 2023

Vya Domus said:
This doesn't really matter, those pumps have molex/sata power, the cable is just for speed control.

Not all of them do.

Assimilator · Nov 6, 2023

AusWolf said:
Not all of them do.

Any discrete pump that draws over ~12W is going to go down the Molex/SATA power route because there's no guarantee it won't be paired with an older board that will literally catch fire if more than 1A is requested from the fan header. AIOs don't take nearly as much power as discrete pumps, hence why they can get away with running entirely off a header.

HBSound · Nov 7, 2023

EKWB DCC Pump Info..

Vya Domus said:
This doesn't really matter, those pumps have molex/sata power, the cable is just for speed control.

So if the PWM is controlling the speed of the pump - only?

And any kind of power is coming from the Molex/PSU - only? So technically I could double or triple the wattage on the motherboard because the wattage is coming from the PSU via Molex - right?

AusWolf · Nov 7, 2023

HBSound said:
So if the PWM is controlling the speed of the pump - only?

And any kind of power is coming from the Molex/PSU - only? So technically I could double or triple the wattage on the motherboard because the wattage is coming from the PSU via Molex - right?

Yes.

System Name	Holiday Season Budget Computer (HSBC)
Processor	AMD Ryzen 7 7700X
Motherboard	MSi PRO B650M-A WiFi
Cooling	be quiet! Dark Rock 4
Memory	2x 16 GB Corsair Vengeance EXPO DDR5-6000
Video Card(s)	Sapphire Pulse Radeon RX 6500 XT 4 GB
Storage	2 TB Corsair MP600 GS, 2 TB Corsair MP600 R2, 4 + 8 TB Seagate Barracuda 3.5"
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Mouse	Logitech MX Master 2S
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Software	Windows 10 Pro

System Name	Good enough
Processor	AMD Ryzen R9 7900 - Alphacool Eisblock XPX Aurora Edge
Motherboard	ASRock B650 Pro RS
Cooling	2x 360mm NexXxoS ST30 X-Flow, 1x 360mm NexXxoS ST30, 1x 240mm NexXxoS ST30
Memory	32GB - FURY Beast RGB 5600 Mhz
Video Card(s)	Sapphire RX 7900 XT - Alphacool Eisblock Aurora
Storage	1x Kingston KC3000 1TB 1x Kingston A2000 1TB, 1x Samsung 850 EVO 250GB , 1x Samsung 860 EVO 500GB
Display(s)	LG UltraGear 32GN650-B + 4K Samsung TV
Case	Phanteks NV7
Power Supply	GPS-750C

Processor	Rocket Lake Core i5 11600K @ 5 Ghz with PL tweaks
Motherboard	MSI MAG Z490 TOMAHAWK
Cooling	Thermalright Peerless Assassin 120SE + 4 Phanteks 140mm case fans
Memory	32GB (4 x 8GB SR) Patriot Viper Steel 4133Mhz DDR4 @ 3600Mhz CL14@1.45v Gear 1
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Power Supply	Seasonic CORE GM650w Gold Semi modular
Mouse	Coolermaster Storm Octane wired
Keyboard	Element Gaming Carbon Mk2 Tournament Mech
Software	Win 10 Home x64

System Name	Good enough
Processor	AMD Ryzen R9 7900 - Alphacool Eisblock XPX Aurora Edge
Motherboard	ASRock B650 Pro RS
Cooling	2x 360mm NexXxoS ST30 X-Flow, 1x 360mm NexXxoS ST30, 1x 240mm NexXxoS ST30
Memory	32GB - FURY Beast RGB 5600 Mhz
Video Card(s)	Sapphire RX 7900 XT - Alphacool Eisblock Aurora
Storage	1x Kingston KC3000 1TB 1x Kingston A2000 1TB, 1x Samsung 850 EVO 250GB , 1x Samsung 860 EVO 500GB
Display(s)	LG UltraGear 32GN650-B + 4K Samsung TV
Case	Phanteks NV7
Power Supply	GPS-750C

System Name	Holiday Season Budget Computer (HSBC)
Processor	AMD Ryzen 7 7700X
Motherboard	MSi PRO B650M-A WiFi
Cooling	be quiet! Dark Rock 4
Memory	2x 16 GB Corsair Vengeance EXPO DDR5-6000
Video Card(s)	Sapphire Pulse Radeon RX 6500 XT 4 GB
Storage	2 TB Corsair MP600 GS, 2 TB Corsair MP600 R2, 4 + 8 TB Seagate Barracuda 3.5"
Display(s)	Dell S3422DWG, 7" Waveshare touchscreen
Case	Kolink Citadel Mesh black
Audio Device(s)	Logitech Z333 2.1 speakers, AKG Y50 headphones
Power Supply	Seasonic Prime GX-750
Mouse	Logitech MX Master 2S
Keyboard	Logitech G413 SE
Software	Windows 10 Pro

System Name	Firelance.
Processor	Threadripper 3960X
Motherboard	ROG Strix TRX40-E Gaming
Cooling	IceGem 360 + 6x Arctic Cooling P12
Memory	8x 16GB Patriot Viper DDR4-3200 CL16
Video Card(s)	MSI GeForce RTX 4060 Ti Ventus 2X OC
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Display(s)	3x AOC Q32E2N (32" 2560x1440 75Hz)
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Mouse	Logitech G602
Keyboard	Logitech G613
Software	Windows 10 Professional x64

Understanding the MSI Motherboard - PWM Fan connectors

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