Anyone that has a Spike pinball machine knows that the fan is WAY TOO LOUD and really annoying, especially in a home environment.

This fan kit is designed to replace the stock 34.6dB fan in Stern Spike power supplies to make it almost silent. This replacement 12.8dB fan has less CFM (airflow) than the Stern one, but the practical difference is that  the fan simply runs a bit longer to drop the temp back down to ~104F or less once the temperature in the power supply turns it on. In testing with this fan installed on multiple machines, the RSP-500-48 power supply never exceeded ~122F (the power supply critical shutdown threshold is ~158F), however, all possible pinball machine configurations cannot be known, so you are installing this kit at your own risk.

The kit includes the fan with custom wire length and connector, two thread-cutting screws, and illustrated installation instructions.
Another great product from The Pinball Monk!

See secondary picture for compatibility list.

1. How loud is the Stern Fan?  How quiet is the Pinmonk one?
   Meanwell has used two different fans in the power supplies Stern uses, both are very loud. The current one is the loudest of the two. Depending on which one is in yours, the noise is between approximately 34dB and 38dB.  The Pinmonk fan is less than 13dB.  Since decibels aren't linear that's about 10x quieter.
2. Since this fan pushes less air, does the fan come on more often?
   The Meanwell power supply Stern is using has a thermal scheme that dictates when the fan comes on, and when it turns off. For the 500w version, the fan comes on when it hits 122 degrees inside the power supply and stays on until the temperature comes down below 104 degrees, when it turns off. So the fact that the Pinmonk fan kit pushes less air than the stock fan just means that it runs slightly longer when it does come on to bring it down to <104F again. It does not mean the fan comes on more often than a stock fan.
3. But if the fan's quiet, how will I know when it fails? Will it burn up my power supply if it isn't cooled?
   If the fan fails, the worst that can happen is the power supply will gradually throttle power due to the built-in failsafe system on the power supply. The power supply's failsafe begins throttling power if the temperature exceeds 122F and if the temperature continues rising (if the fan failed, for example) then a power-off trigger kicks in at 158F to protect the power supply and machine it's attached to. There is no danger of a failed fan damaging a machine or the power supply as a result. See the temp throttling chart for the power supply on the photo attached to see the throttling curve. If a fan fails (and we don't know of a Pinmonk quiet fan kit failing in more than 3 years of selling these), you'd just replace the fan and the power supply would be back in business. It would not "burn up."