A year ago I had looked into alternative air cooling options for GPUs since I wanted something quieter than the blower fans on my reference 980s but since I'm running SLI in a small case I still wanted them to exhaust out the rear and I came across these interesting air movers called SynJets, developed by a company called Nuventix (which was acquired by Aavid Thermalloy)
Here's a overview of how it works:
Basically, it's like a pair of bellows, a diaphragm inside the unit oscillates back and forth and on the downstroke it moves quickly and expels a high-velocity burst of air out the nozzle, then on the upstroke it moves slowly to intake air into the chamber.
This has a few advantages, namely the lack of bearing that will wear out and more compact form factors.
The main question I had was noise level and performance and since there wasn't an easy way to mount one to a GPU I put the idea on hold.
But recently @Tek Everything reviewed the Corsair H5 SF and a major complaint he had with the unit was the blower fan was way too loud, even at idle. There's not too many fan replacement options due to the form factor of the radiator though, which was originally designed by Asetek to be used with 40mm fans so it could fit in a 1U server chassis.
So I started thinking if it would be possible to combine one of these SynJets with the radiator from the H5 SF:
It seemed feasible and I had been curious about using these things for SFF cooling for some time so I went ahead and ordered two for testing.
Here is one next to a 120mm Gentle Typhoon
Next I had to crimp pins onto the wire harnesses (which are sold separately BTW) so they could be plugged into a motherboard header.
This is a rough noise comparison between the Noctua NF-P12 PWM and the Aavid Thermalloy SynJet XFlow X42 12V PWM.
Note: This was recorded using an iPhone 6 from ~250mm (10in) away. The ambient noise level was pretty low so the white noise you hear (especially in the SynJet at 50% clip) is just that, the noise floor of the microphone.
Not the quietest or smoothest sounding things in the world but not terrible, especially at lower speeds.
One interesting thing I noticed about them during this testing is the airflow is very focused. At about .5m away the "beam" of air is only about .25m across. Measured perpendicular to the plane of the nozzles.
Then I did some brief testing on my i7 4771 in my M1 with the Noctua C12 heatsink:
Even with the SynJets at full speed the CPU would thermal throttle after several minutes of Prime95 Blend 8-threads, though only to 3.6-3.8GHz from the normal 3.9GHz. Ambient was ~20°C and the CPU was getting to 78°C. This arrangement is far from ideal though since most of the heatsink array isn't getting airflow from the SynJets.
So on to a setup more suited for the SynJets:
Here two SynJet XFlow X42s are paired with an Asetek OEM 92mm water cooler.
System specs:
Now we're starting to make progress! Of course this is with an open air setup but it's looking much better. I was worried after the poor performance with my M1 testing that these wouldn't work for anything but very low wattage chips.
Next step is to order a Corsair H5 SF so I can test it and take measurements in order to design a 3d printed bracket to mount one of the SynJets to it in place of the stock blower fan.
Here's a overview of how it works:
Basically, it's like a pair of bellows, a diaphragm inside the unit oscillates back and forth and on the downstroke it moves quickly and expels a high-velocity burst of air out the nozzle, then on the upstroke it moves slowly to intake air into the chamber.
This has a few advantages, namely the lack of bearing that will wear out and more compact form factors.
The main question I had was noise level and performance and since there wasn't an easy way to mount one to a GPU I put the idea on hold.
But recently @Tek Everything reviewed the Corsair H5 SF and a major complaint he had with the unit was the blower fan was way too loud, even at idle. There's not too many fan replacement options due to the form factor of the radiator though, which was originally designed by Asetek to be used with 40mm fans so it could fit in a 1U server chassis.
So I started thinking if it would be possible to combine one of these SynJets with the radiator from the H5 SF:
It seemed feasible and I had been curious about using these things for SFF cooling for some time so I went ahead and ordered two for testing.
Here is one next to a 120mm Gentle Typhoon
Next I had to crimp pins onto the wire harnesses (which are sold separately BTW) so they could be plugged into a motherboard header.
This is a rough noise comparison between the Noctua NF-P12 PWM and the Aavid Thermalloy SynJet XFlow X42 12V PWM.
Note: This was recorded using an iPhone 6 from ~250mm (10in) away. The ambient noise level was pretty low so the white noise you hear (especially in the SynJet at 50% clip) is just that, the noise floor of the microphone.
Not the quietest or smoothest sounding things in the world but not terrible, especially at lower speeds.
One interesting thing I noticed about them during this testing is the airflow is very focused. At about .5m away the "beam" of air is only about .25m across. Measured perpendicular to the plane of the nozzles.
Then I did some brief testing on my i7 4771 in my M1 with the Noctua C12 heatsink:
Even with the SynJets at full speed the CPU would thermal throttle after several minutes of Prime95 Blend 8-threads, though only to 3.6-3.8GHz from the normal 3.9GHz. Ambient was ~20°C and the CPU was getting to 78°C. This arrangement is far from ideal though since most of the heatsink array isn't getting airflow from the SynJets.
So on to a setup more suited for the SynJets:
Here two SynJet XFlow X42s are paired with an Asetek OEM 92mm water cooler.
System specs:
- Intel i3-2120 (65W TDP)
- Asetek OEM 92mm AIO
- 8GB RAM
- ASUS P8P67 Pro motherboard
- Radeon HD 5450
- Fractal Design Tesla R2 500W PSU
- Some random SSD
- Windows 10
Now we're starting to make progress! Of course this is with an open air setup but it's looking much better. I was worried after the poor performance with my M1 testing that these wouldn't work for anything but very low wattage chips.
Next step is to order a Corsair H5 SF so I can test it and take measurements in order to design a 3d printed bracket to mount one of the SynJets to it in place of the stock blower fan.
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