Search for posts in these Forums by JDW on the subject of SE/30, and SilenX or 'iXtrema'. JDW spent quite some time evaluating fans for the SE/30, and strongly recommended the SilenX as a result. They use not ball-bearing but more up-to-the-minute fluid-dynamic bearings. There are those in various modders forums who inveigh against SilenX, but little hard evidence that the fans do not serve their purpose well.
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