[SOLVED] Cooler Master ML240L - Question regarding fans / Motherboard hook-up

[Brendman]

Hello everyone!

Back in September, I built a friend and I built my new PC. Lately, I've realized that the Cooler Master ML240L V2 fans have been getting incredibly noisy - it almost sounds like a rattling sound. After doing some research, it seems like this is a common issue, so i'm looking to purchase some new fans to replace them with.

However, during my research, I noticed that it looks like we connected the pump to the CPU_OPT spot on the Motherboard (it doesn't look like there is a designated 'pump' spot). I then noticed that in the BIOS, that this particular port isn't set to have constant power, it looks like it's on a normal fan curve.

My question is - should I set this to be 'Full Power' all the time, in the BIOS? I have seen people mention PWM/DC, but it doesn't look like my BIOS has that option (as far as I can tell).

Below is the Motherboard specs, so that maybe someone with any experience in these particular BIOS can point me in the right direction of what to do:

GIGABYTE X570 UD AM4 ATX
COOLMAST ML240L RGB V2 CPU COOLER

Also, if anyone has any recommendation on replacement fans for the ML240L, that'd be great! I'm just looking for something that's quiet and still efficient - RGB is not required.

Thank you everyone!

 

[tennis2]

Yes, pump should be at constant 100% duty cycle.

Pick any 120mm fans with good/high static pressure. What's your budget for fans and what country are you shopping in?

 

[Brendman]

Thanks for the response! Okay, so in the BIOS I would set the CPU_OPT to 'Full Speed'? In this BIOS specifically, the fan 'section' is called 'Smart Fan 5'.


And as for fans, I don't necessarily have a budget, anything under ~30 per fan is fine. I did read that the Noctua NF-F12 PWM fans are great, so I was thinking of going with those.

This is to the U.S., as well.

 

[Paperdoc]

Agreed, you SHOULD arrange for the pump to run full speed all the time. There are two ways to do this. See your mobo manual, p. 24 for SmartFan 5 options. You have to select the correct header to adjust. One method is to set the Fan Speed Control option to Full Speed. The other way is to use any setting at that option, and skip down to Fan Control Mode. There you set it to PWM Mode, even though this is a 3-pin pump connector. This uses a quirk of fan designs: if you plug a 3-pin fan into a mobo header that is using PWM Mode, that fan will always run full speed. That's exactly what you want for the pump.

The Noctua NF-F12 PWM fans are a good choice. The have an excellent reputation for low noise, long life and good air flow, and the backpressure rating of that model is quite suitable for rad fans use. Just a small note. Noctua ships many of their fans with a tiny accessory called a "Low Noise Adapter" that can be inserted into the fan's power connector. They are useful ONLY if you have NO way to control fan speed and need them to slow down permanently. Do NOT use that item when you connect your new fans to the mobo CPU_FAN header. It will only interfere and limit your fan's cooling ability at high workloads, just when you need it.