Recently at work we discovered a noisy fan inside a Netgear GS516T Gigabit switch. Sometimes when fan bearings start to fail they can be silenced with a little percussive maintenance. Despite our best efforts to tap and bang on the switch we were unable to cure its disease.

In an effort to get warranty service I looked up the original purchase order for this switch. Although it was far beyond its service expiration, I discovered that we paid $1332 for it when 1000Base-T was brand new in 2002. Ouch! This was probably the first gigabit hardware our building had ever seen. Considering an equivalent replacement now costs around $189, I didn’t want to see this unit die of heatstroke. This switch has since been demoted, so with nothing to lose I decided to take it apart and see if I could fix it myself. Click to continue…

I was hoping the noisy fan would be one of the two large exhaust units along the back edge of the housing. Unfortunately it was not.

Inside this switch are two boards, each with two processors to control the corresponding banks of RJ-45 Ethernet ports on the front panel. Each of these four processors has its own heatsink fan combo. I tested each by spinning them with compressed air, and only one had the bad bearing.

The fan is a tiny Sunon model that runs off of 5V DC from the main board.

I was lucky enough to find the exact part from an online retailer that sells refurbished surplus.

The top board lifts off and is partially held down by these pinned connectors.

Look at all of those heatsinks. I had no idea this thing gets so hot.

The hardest task in replacing this part involved removing the existing heatsink. It was held on with an adhesive that took quite a bit of acetone to soften. In order to get the acetone under the heatsink I had to remove the fan.

The fan did not respond well to blunt force trauma.

This is one of the four cores inside the switch housing.

Attaching the new unit was easy enough, but the power connector that shipped with the replacements was much smaller than the original.

Our electronics lab was fresh out of crimp connectors of this type so I had to improvise. Rather than hot-wire the connection, I opted to splice the wires from the original.

This is what I ended up with, which looks almost like it was never replaced. We even had matching heat shrink tubing. I’m very pleased with how this turned out.

In a stroke of brilliance I decided to preventively replace two fans instead of only one. The second unit did not go so well. I accidentally cut the wire on the wrong end, and ended up having to take a similar connector and rig it together.

It came out looking like this. I am not as happy with the subsequent craftsmanship, but the fan still spins so I can’t complain.

When it was all said and done, the entire project cost around $27 in parts. I found the adhesive pads on eBay and the fan parts by doing extensive Google Products search. The fans are silent and the switch works as well as it did before. Success!