Definition updates cause fans to Whine Loudly...! in Emsisoft Anti-Malware Home Posted April 5, 2012 · Report reply There are a few reasons why your computer's fans would be making a lot of noise. One could be bearing damage that causes noise when the fans spins faster, another could be too much dust in the fans, and there's also the possibility of an electrical issue. A bearing issue cannot be fixed, however if you have a good silicon based lubricant then many fans have a way to add lubricant in order to extend the lifespan of the fans. If it's just dust, then that can be removed with a can of compressed air. A power issue can usually be solved by plugging your computer in through a UPS (Uninterruptible Power Supply). Most UPS units will filter power, and this can help with a lot of issues (I've seen computers perform better when connected to a UPS, speakers emit less static when the volume was turned up, and various other small improvements when plugged in to a UPS). Of course, even if any of those suggestions resolve the issue you are experiencing, I'm sure you'll still be wondering why the update process causes the fans to make noise. It's possible that some extra processing power is required for the updates, and this can cause the processor to heat up a little bit, which causes the fans to spin faster. How much your processor heats up depends on what processor your computer has and how good the heatsink and airflow inside the computer are.