Hi I am planning to replace the three fans in a GS752TPP to make it a bit quieter when running.
The fans in the system are: PVA040F12N
The fans that I plan to install are: Noctua NF-A4x20
The concern I have is of course the cooling performance after the swap.
The Noctua NF-A4x20 has a power draw of 12V * .05 A
The PVA040F12N power draw is 12V * .28 A
Since this is such a large difference I’m slightly worried how the Noctua fans are going to do. The airflow of the Noctua fans according to there site is Airflow 9,4 m³/h.
I can’t find any info from the stock fans to compare.
Any help and input is appreciated.
How many ports active on the switch, and any PoE?
I would bet my life on it being fine. It has quite a high operating temp and supports PoE+ etc. It would be designed to operate at max ambient with all ports 100% bandwidth, etc
Thats good to know!
Right now I’m using 5 ports but I will use more in the future with 2 being Poe.
I will also be using PoE on many of the ports to power ESP devices, cameras, PoE Passthrough Switches, ect…
My idea is to use this switch to power everything that won’t be next to a Power Outlet with adapters like this.
The fans are usually quiet most of the time but they do spin up occasionally when I max out my internet at 1Gbps. It hasn’t been loud but its not really under a heavy load.
To make the noise more tolerable in an office setting for our switches, I customized the top cases. I cut openings in them and then printed mounts to bolt the fans together, along with tabs to secure them to the case.
The cutting process is quite rough, usually using a grinder or Dremel. Therefore, the fan support on the bottom is tapered with a step. This design helps to self-center the fans and keep them in place, preventing them from falling out if the switch is turned upside down, while also compensating for the rough tolerances.
For this setup, I used Corsair ML120 fans and placed filters on top for safety.
This switch is a Mellanox SB-7790, and I selected the B2F flow unit. It’s important to note that the rear doors close when you remove the original fans, so air is primarily forced to flow through the front, but not much through the PSU.
We have another Mellanox SB-77XX switch in a full-size case. In that case, the PSU fan spins at max RPM if it doesn’t detect the main fans connected. Therefore, we made an additional cut over the PSU area and added a duct to direct airflow through the PSU and then out the back.
I’ve attached a photo from the test fit. Since this modification increases the unit to 2U, I placed the cable panel above it, allowing the fans to get free airflow without leaving the appearance of an open rack slot above it but leaving space for fans and airflow.
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