There is a design flaw and no obvious way around it.
Look closely at the image and you will see that the fan is larger than the heatsink. Behind the mounting holes on the fan are four rubber mounting posts which slide into grooves on the heatsink.
These rubber mounts are not easily slid into the grooves, especially after it is mounted in the computer, as there is virtually no room around it. I found that applying a small amount of silicon grease helped no end but it is still a difficult job.
Unfortunately, the rubber mounts can’t be slid in too far because of the spacing of the mounting holes on the 120mm fan. In the photo, all looks well, but mounted on the CPU and run, the pressure from the fan can and does force the fan away from the heatsink. This results in two of the mountings breaking free of the heatsink, at which point the pressure of air swings the fan away from the heatsink on the remaining two mounts.
Not cool, literally.
I discovered this yesterday after removing the cover for a dust removal session yesterday. First thoughts were to mount a 100mm fan, but the spacing of the grooves in the heatsink is too great.
Of the tower type heatsinks, the HA2 version has a similar fitting, but the heatsink itself is way thinner, and the HA3 doesn’t have rubber mountings at all. It uses wire clips which are not vibration free. The wire fittings from the HA3 will not work because the HA4 heatsink does not have the grooves to allow for them.
Time to contact Silenx support, methinks.
OK. I have had a reply from the manufacturer.
- Bend the fins to trap the rubber mounts – If I do thatI will never be able to do anything at all with the fan in situ, e.g. replacing in the event of failure..
- Tape the fan to the sides of the heatsink – as in duct tape? Will that be vibration free?
Maybe I will leave things as they are, and just check now and again..