Help. AIO Pump annoying buzz

[heedtheninja67]

I have an Asetek 550LC, which is the OEM Corsair H60. There's tons of topics/videos about how these Corsair Hydro pumps buzz and there's no definitive solution. Some have RMA'd multiple times with the same issue. Some were able to undervolt the pump with success. My current setup is:

MSI Z170I Mini-iTX motherboard
Pump in CPU_FAN header (0.2A)
Radiator + Case fans in SYS_FAN header via 3-pin splitter (0.6A)

I've tried controlling the CPU_FAN header with the BIOS, but it seems it only controls with 4 pins, because it stays at 100% regardless of what I put the curve at. I've tried switching fan headers, then my fans go full blast in CPU_FAN, so I can't hear the pump to check anyway.

One thing to note is that it seems the buzzing loudness comes and goes. There's always a light hum, which is fine. This isn't air bubbles, it's definitely an electrical sound. Any insight is appreciated.

[Tam3n]

I had this issue with my Corsair H100... I put a couple of diodes in series with the molex power wire to lower the input voltage, solved the grinding noise.

[heedtheninja67]

8 hours ago, Tam3n said:

I had this issue with my Corsair H100... I put a couple of diodes in series with the molex power wire to lower the input voltage, solved the grinding noise.

May I ask what your connection chain looked like and what kind of electrical work was involved?  I have 2 LEDs that are split from a molex connector that aren't being used, but did you mean resistor?  I see you can buy 3-pins with a resistor in-line, but the resistance seems as bit high.  

 

Thanks.

[Tam3n]

8 hours ago, heedtheninja67 said:

May I ask what your connection chain looked like and what kind of electrical work was involved?  I have 2 LEDs that are split from a molex connector that aren't being used, but did you mean resistor?  I see you can buy 3-pins with a resistor in-line, but the resistance seems as bit high.  

 

Thanks.

I don't remember specifically (been like 3 years), but anyway, diodes always have a voltage drop of 0.7 V. If you put two in series, you would get total of 1.4 V reduction in voltage. Resistor's voltage drop depends on the current, so it is not as simple to control the voltage drop as in the case of a diode. LED being a Light Emiting Diode should also work for this purpose, but normal LEDs might not be able to take the current.

 

Molex connector should have a yellow (+12 V), a red (+5 V) and two black (grounds) wires going into it. If you have all black cables, use a multimeter or lookup the layout on the net. The pump uses the yellow (+12 V) as input power source, so you need to cut this wire and add your diode(s) in series with this. The current is going into pump, so the diode's orientation need to be so that they allow current in that direction, otherwise they just block the current, and you need to flip them around. If you have a spare PSU you could experiment with it by just plugging the pump molex to it (12 V is totally safe to just keep the PSU on and connect the wires with your fingers).

 

Someone on the net has measured that the H100i pump only uses like ~2 Watts which means the current would be around 0.2 A, which should be fine for a basic diode, but LEDs on the other hand might be rated for only 20 mA, so be aware of that. If you do it well, just circling the wires around the diode's wires and "electrical-taping it together" should be fine, but if you have a solderer use that once you have tested out what works. I was lucky as we have all kinds of electrics parts and such lying around in my parents house, so i just picked some random diodes I found and they have worked well. They are really cheap anyway, so if you can overcome the trouble go crap some from a electronics shop etc.

[FrankV]

Given it's a re-branded Corsair AIO have you tried to control the pump with Corsair LINK? Might be worth a shot. I think the speed is controlled through the USB interface not the header

[heedtheninja67]

Thanks Tam3n.  The LED's prob won't work... the pump is rated at 2.1W.  One of my fan's came with a small 3 inch 3-pin extension.  I should be able to solder on a diode or two without ripping into the pump.  Power supply is reading 12.19V, so two diodes will keep that at about 90% of the rated 12V.

 

On 1/20/2017 at 3:33 PM, FrankV said:

Given it's a re-branded Corsair AIO have you tried to control the pump with Corsair LINK? Might be worth a shot. I think the speed is controlled through the USB interface not the header

I tried the software then realized all the extra stuff you need.  I have a SFF build so that probably won't work well.