3COM:
Fixing a noisy Switch
Turns out that one of the routers at the lab is *extremely* noisy when powered. So they gave it to me to fix! Goody!
![](images/3COM/3COMFront.jpg)
The unit is an older 3COM unit (SuperStack II Port Switch Hub).
![](images/3COM/3COMBottom.jpg)
Here's a shot of the bottom of the unit
![](images/3COM/3COMScrewDetail.jpg)
Upon inspection, it appears that the unit is held together with just a couple of TORX screws located at the bottom of the unit.
![](images/3COM/NewToolKit.jpg)
Luckily, just last week I gave myself a little XMAS present...tools!
One of my little purchases was a complete micro-screwdriver kit, which handily included a TORX set, which had already turned in to be very handy in a couple of other situations. Long story short, getting the screws out of the 3COM was a doodle. Easy! I thought that once the TORX screws were removed it would be easy to get the plastic cover off....but no!
Turns out that getting the plastic casing off of a 3COM chassis is a complete pain in the neck!
Eventually, I got the darn thing off by *carefully* levering the little clips away from the chassis and *slowly* sliding the casing up.
With the casing removed, getting the fan out was simple. Just unplug it from the motherboard and gently wiggle it out of place.
Next, a quick trip to Ap Liu Gai to find a replacement fan and then a quick re-assembly
![](images/3COM/MainBoard01.jpg)
A shot of the main board and the connector for the fan highlighted
![](images/3COM/MainBoard02.jpg)
Detailed shot of the fan connector. Note polarity of connector. One way
![](images/3COM/NewFan01.jpg)
The new fan. Lovely but can you see what's wrong with it?
![](images/3COM/OldFan01.jpg)
To refresh your memory, here is a shot of the old fan...
![](images/3COM/WrongWay01.jpg)
Yup...the connectors are the WRONG WAY around
![](images/3COM/Rewired01.jpg)
Alright, inverting the leads is not normally recommended...but...
![](images/3COM/Rewired02.jpg)
Wires re-badged to prevent any misunderstandings in the future....
![](images/3COM/Rewired03.jpg)
The new fan installed and 3COM is ready for the re-assembly!
SOLVED