Silent PC Review spends a lot of effort choosing components which offer a great performance but do not create a lot of noise and their latest sytem is a perfect example.  Even with a pair of air cooled GTX 970's and an i5-4690K this system only hit 23dBA under load, quiet enough for SPCR to confirm their 970's suffer from coil whine.  The sound came primarily from the GPUs as you would expect so it is possible that finding a very quiet radiator and watercooling them might reduce the sound produced even further.  It just goes to show how much quieter air cooling has become from the days of screaming 40mm Deltas.

"For our 8th Quiet Gaming PC Build Guide, we take on the challenge of two high-end video cards in an SLI configuration featuring a pair of Zotac GTX 970s in the SilverStone Fortress FT05 case."

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Systems